diff --git a/CHANGELOG.md b/CHANGELOG.md
index 475f4995b..079a5adec 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,15 @@
 # Changelog Fab-manager
 
+## v5.3.10 2022 April 12
+
+- Updated generate invoice reference method
+- Set invoice reference is required
+- Fix a bug: unable to show machine availability slot for admin
+- Fix a bug: unable to confirm modification of reservation for client
+- Fix a bug: unable to show deleted user in reservation slot
+- Fix a bug: race condition on invoice after payment (concerning payment schedules) https://app.clickup.com/t/25zpmn1
+- Fix a bug: form maxlength count to exclude spaces and newline
+
 ## v5.3.9 2022 April 01
 
 - Optimise sql query, avoid to N+1
diff --git a/app/frontend/src/javascript/controllers/machines.js.erb b/app/frontend/src/javascript/controllers/machines.js.erb
index 26f83c140..cacd5cd1a 100644
--- a/app/frontend/src/javascript/controllers/machines.js.erb
+++ b/app/frontend/src/javascript/controllers/machines.js.erb
@@ -499,7 +499,7 @@ Application.Controllers.controller('ReserveMachineController', ['$scope', '$tran
         slotId: $scope.events.modifiable.slot_id,
         borderColor: $scope.events.modifiable.borderColor,
         user: angular.copy($scope.events.modifiable.user),
-        title: $scope.currentUser.id === $scope.events.modifiable.user.id ? _t('app.logged.machines_reserve.i_ve_reserved') : _t('app.logged.machines_reserve.not_available')
+        title: (!$scope.events.modifiable.user || $scope.currentUser.id === $scope.events.modifiable.user.id) ? _t('app.logged.machines_reserve.i_ve_reserved') : _t('app.logged.machines_reserve.not_available')
       };
 
       $scope.events.modifiable.backgroundColor = 'white';
diff --git a/app/frontend/src/javascript/directives/cart.js b/app/frontend/src/javascript/directives/cart.js
index da8865547..968b169e7 100644
--- a/app/frontend/src/javascript/directives/cart.js
+++ b/app/frontend/src/javascript/directives/cart.js
@@ -564,7 +564,12 @@ Application.Directives.directive('cart', ['$rootScope', '$uibModal', 'dialogs',
               return dialogs.confirm({
                 templateUrl: '/shared/confirm_modify_slot_modal.html',
                 resolve: {
-                  object () { return $scope.slot; }
+                  object () {
+                    if ($scope.slot.user && !$scope.slot.user.name) {
+                      $scope.slot.user.name = _t('app.shared.confirm_modify_slot_modal.deleted_user');
+                    }
+                    return $scope.slot;
+                  }
                 }
               }
               , function (type) {
diff --git a/app/frontend/templates/admin/calendar/calendar.html b/app/frontend/templates/admin/calendar/calendar.html
index c760602ef..637579fca 100644
--- a/app/frontend/templates/admin/calendar/calendar.html
+++ b/app/frontend/templates/admin/calendar/calendar.html
@@ -80,7 +80,8 @@
       <div class="widget-content no-bg auto wrapper" ng-class="{'reservations-locked': availability.lock}">
         <ul class="list-unstyled" ng-if="reservations.length > 0">
           <li ng-repeat="r in reservations" class="m-b-xs" ng-class="{'reservation-canceled':r.canceled_at}">
-            {{r.user.name}}
+            <span ng-if="r.user.name">{{r.user.name}}</span>
+            <span translate ng-if="!r.user.name">{{ 'app.admin.calendar.deleted_user' }}</span>
               - <span class="label reservation-time">{{ r.start_at | amDateFormat:'LLL' }} - {{ r.end_at | amDateFormat:'LT' }}</span>
               - <span class="label label-success text-white">{{r.reservable.name}}</span>
               <span class="btn btn-warning btn-xs" ng-click="cancelBooking(r)" ng-if="!r.canceled_at"><i class="fa fa-times red"></i></span>
diff --git a/app/frontend/templates/admin/invoices/settings/editReference.html b/app/frontend/templates/admin/invoices/settings/editReference.html
index 021d62494..9985cab17 100644
--- a/app/frontend/templates/admin/invoices/settings/editReference.html
+++ b/app/frontend/templates/admin/invoices/settings/editReference.html
@@ -19,6 +19,7 @@
       <div class="model">
         <h4 translate>{{ 'app.admin.invoices.model' }}</h4>
         <input type="text" class="form-control" ng-model="model">
+        <span class="help-block error" ng-show="model.trim() === ''" translate>{{ 'app.admin.invoices.invoice_reference_is_required' }}</span>
       </div>
       <div class="help">
         <h4 translate>{{ 'app.admin.invoices.documentation' }}</h4>
@@ -28,7 +29,7 @@
     </div>
   </div>
   <div class="modal-footer">
-    <button class="btn btn-warning" ng-click="ok()" translate>{{ 'app.shared.buttons.confirm' }}</button>
+    <button class="btn btn-warning" ng-click="ok()" ng-disabled="model.trim() === ''" translate>{{ 'app.shared.buttons.confirm' }}</button>
     <button class="btn btn-default" ng-click="cancel()" translate>{{ 'app.shared.buttons.cancel' }}</button>
   </div>
 </div>
diff --git a/app/frontend/templates/admin/plans/_form.html b/app/frontend/templates/admin/plans/_form.html
index 152c6ae73..278549909 100644
--- a/app/frontend/templates/admin/plans/_form.html
+++ b/app/frontend/templates/admin/plans/_form.html
@@ -7,6 +7,7 @@
            name="plan[base_name]"
            class="form-control"
            ng-maxlength="24"
+           ng-trim="false"
            ng-model="plan.base_name"
            required="true"/>
     <span class="help-block error" ng-show="planForm['plan[base_name]'].$dirty && planForm['plan[base_name]'].$error.required" translate>{{ 'app.shared.plan.name_is_required' }}</span>
diff --git a/app/frontend/templates/admin/plans/edit.html b/app/frontend/templates/admin/plans/edit.html
index f7084c259..252036465 100644
--- a/app/frontend/templates/admin/plans/edit.html
+++ b/app/frontend/templates/admin/plans/edit.html
@@ -93,6 +93,13 @@
                 </tr>
                 </tbody>
               </table>
+              <ul>
+              <li ng-repeat="(key, errors) in planForm.$error track by $index"> <strong>{{ key }}</strong> errors
+                <ul>
+                  <li ng-repeat="e in errors">{{ e.$name }} has an error: <strong>{{ key }}</strong>.</li>
+                </ul>
+              </li>
+              </ul>
 
               <div class="panel-footer no-padder">
                   <input type="submit" value="{{ 'app.shared.buttons.confirm_changes' | translate }}" class="r-b btn-valid btn btn-warning btn-block p-lg btn-lg text-u-c" ng-disabled="planForm.$invalid"/>
diff --git a/app/frontend/templates/admin/settings/text.html b/app/frontend/templates/admin/settings/text.html
index 4165b445a..8ecc824d7 100644
--- a/app/frontend/templates/admin/settings/text.html
+++ b/app/frontend/templates/admin/settings/text.html
@@ -13,6 +13,7 @@
                  ng-required="true"
                  ng-minlength="minLength"
                  ng-maxlength="maxLength"
+                 ng-trim="false"
                  ng-readonly="readOnly">
       </div>
   </div>
diff --git a/app/frontend/templates/admin/trainings/modal_edit.html b/app/frontend/templates/admin/trainings/modal_edit.html
index 0d3969227..a4171f2f1 100644
--- a/app/frontend/templates/admin/trainings/modal_edit.html
+++ b/app/frontend/templates/admin/trainings/modal_edit.html
@@ -4,7 +4,7 @@
 <div class="modal-body">
   <form name="trainingForm" novalidate>
     <div class="form-group" ng-class="{'has-error': trainingForm['training[description]'].$dirty && trainingForm['training[description]'].$invalid }">
-      <textarea name="training[description]" class="form-control" placeholder="{{ 'app.admin.trainings.describe_the_training_in_a_few_words' | translate }}" ng-model="training.description" ng-maxlength="255"></textarea>
+      <textarea name="training[description]" class="form-control" placeholder="{{ 'app.admin.trainings.describe_the_training_in_a_few_words' | translate }}" ng-model="training.description" ng-maxlength="255" ng-trim="false"></textarea>
       <span class="help-block" ng-show="trainingForm['training[description]'].$dirty && trainingForm['training[description]'].$error.maxlength" translate>{{ 'app.admin.trainings.description_is_limited_to_255_characters' }}</span>
     </div>
   </form>
diff --git a/app/frontend/templates/shared/confirm_modify_slot_modal.html b/app/frontend/templates/shared/confirm_modify_slot_modal.html
index eb17c8d0b..bc78c162a 100644
--- a/app/frontend/templates/shared/confirm_modify_slot_modal.html
+++ b/app/frontend/templates/shared/confirm_modify_slot_modal.html
@@ -3,8 +3,8 @@
   <h1 translate>{{ 'app.shared.confirm_modify_slot_modal.change_the_slot' }}</h1>
 </div>
 <div class="modal-body">
-  <p ng-show="currentUser.id === object.user.id" translate>{{ 'app.shared.confirm_modify_slot_modal.do_you_want_to_change_your_booking_slot_initially_planned_at' }} </p>
-  <p ng-show="currentUser.id !== object.user.id" translate translate-values="{NAME: object.user.name}">{{ 'app.shared.confirm_modify_slot_modal.do_you_want_to_change_NAME_s_booking_slot_initially_planned_at' }}</p>
+  <p ng-show="!object.user" translate>{{ 'app.shared.confirm_modify_slot_modal.do_you_want_to_change_your_booking_slot_initially_planned_at' }} </p>
+  <p ng-show="object.user && currentUser.id !== object.user.id" translate translate-values="{NAME: object.user.name}">{{ 'app.shared.confirm_modify_slot_modal.do_you_want_to_change_NAME_s_booking_slot_initially_planned_at' }}</p>
   <p><strong>{{object.start | amDateFormat: 'LL'}} : {{object.start | amDateFormat:'LT'}} - {{object.end | amDateFormat:'LT'}}</strong></p>
 </div>
 <div class="modal-footer">
diff --git a/app/services/availabilities/status_service.rb b/app/services/availabilities/status_service.rb
index 5735466ab..c48ac6d58 100644
--- a/app/services/availabilities/status_service.rb
+++ b/app/services/availabilities/status_service.rb
@@ -18,7 +18,8 @@ class Availabilities::StatusService
 
         slot.id = s.id
         slot.is_reserved = true
-        slot.title = "#{slot.machine.name} - #{@show_name ? r.user&.profile&.full_name : I18n.t('availabilities.not_available')}"
+        user_name = r.user ? r.user&.profile&.full_name : I18n.t('availabilities.deleted_user');
+        slot.title = "#{slot.machine.name} - #{@show_name ? user_name : I18n.t('availabilities.deleted_user')}"
         slot.can_modify = true if %w[admin manager].include?(@current_user_role)
         slot.reservations.push r
 
diff --git a/app/services/payment_document_service.rb b/app/services/payment_document_service.rb
index 0eb975492..1590eff3c 100644
--- a/app/services/payment_document_service.rb
+++ b/app/services/payment_document_service.rb
@@ -6,7 +6,7 @@ class PaymentDocumentService
     def generate_reference(document, date: DateTime.current)
       pattern = Setting.get('invoice_reference')
 
-      reference = replace_invoice_number_pattern(pattern)
+      reference = replace_invoice_number_pattern(pattern, document.created_at)
       reference = replace_date_pattern(reference, date)
 
       if document.is_a? Avoir
@@ -51,7 +51,7 @@ class PaymentDocumentService
         pad_and_truncate(number_of_invoices('global'), match.to_s.length)
       end
 
-      reference = replace_invoice_number_pattern(reference)
+      reference = replace_invoice_number_pattern(reference, invoice.created_at)
       replace_date_pattern(reference, invoice.created_at)
     end
 
@@ -71,26 +71,25 @@ class PaymentDocumentService
     # Returns the number of current invoices in the given range around the current date.
     # If range is invalid or not specified, the total number of invoices is returned.
     # @param range {String} 'day', 'month', 'year'
+    # @param date {Date} the ending date
     # @return {Integer}
     ##
-    def number_of_invoices(range)
+    def number_of_invoices(range, date = DateTime.current)
       case range.to_s
       when 'day'
-        start = DateTime.current.beginning_of_day
-        ending = DateTime.current.end_of_day
+        start = date.beginning_of_day
       when 'month'
-        start = DateTime.current.beginning_of_month
-        ending = DateTime.current.end_of_month
+        start = date.beginning_of_month
       when 'year'
-        start = DateTime.current.beginning_of_year
-        ending = DateTime.current.end_of_year
+        start = date.beginning_of_year
       else
         return get_max_id(Invoice) + get_max_id(PaymentSchedule)
       end
-      return Invoice.count + PaymentSchedule.count unless defined? start && defined? ending
+      ending = date
+      return Invoice.count + PaymentSchedule.count unless defined? start
 
-      Invoice.where('created_at >= :start_date AND created_at < :end_date', start_date: start, end_date: ending).length +
-        PaymentSchedule.where('created_at >= :start_date AND created_at < :end_date', start_date: start, end_date: ending).length
+      Invoice.where('created_at >= :start_date AND created_at <= :end_date', start_date: start, end_date: ending).length +
+        PaymentSchedule.where('created_at >= :start_date AND created_at <= :end_date', start_date: start, end_date: ending).length
     end
 
     ##
@@ -125,20 +124,20 @@ class PaymentDocumentService
     # Replace the document number elements in the provided pattern with counts from the database
     # @param reference {string}
     ##
-    def replace_invoice_number_pattern(reference)
+    def replace_invoice_number_pattern(reference, date)
       copy = reference.dup
 
       # document number per year (yy..yy)
       copy.gsub!(/y+(?![^\[]*\])/) do |match|
-        pad_and_truncate(number_of_invoices('year'), match.to_s.length)
+        pad_and_truncate(number_of_invoices('year', date), match.to_s.length)
       end
       # document number per month (mm..mm)
       copy.gsub!(/m+(?![^\[]*\])/) do |match|
-        pad_and_truncate(number_of_invoices('month'), match.to_s.length)
+        pad_and_truncate(number_of_invoices('month', date), match.to_s.length)
       end
       # document number per day (dd..dd)
       copy.gsub!(/d+(?![^\[]*\])/) do |match|
-        pad_and_truncate(number_of_invoices('day'), match.to_s.length)
+        pad_and_truncate(number_of_invoices('day', date), match.to_s.length)
       end
 
       copy
diff --git a/app/views/api/availabilities/machine.json.jbuilder b/app/views/api/availabilities/machine.json.jbuilder
index 6570c03fe..ab4879c08 100644
--- a/app/views/api/availabilities/machine.json.jbuilder
+++ b/app/views/api/availabilities/machine.json.jbuilder
@@ -18,8 +18,8 @@ json.array!(@slots) do |slot|
   # the user who booked the slot, if the slot was reserved
   if (%w[admin manager].include? @current_user_role) && slot.reservation
     json.user do
-      json.id slot.reservation.user.id
-      json.name slot.reservation.user.profile.full_name
+      json.id slot.reservation.user&.id
+      json.name slot.reservation.user&.profile&.full_name
     end
   end
   json.tag_ids slot.availability.tag_ids
diff --git a/app/views/api/availabilities/spaces.json.jbuilder b/app/views/api/availabilities/spaces.json.jbuilder
index cbf35860e..5661bdd35 100644
--- a/app/views/api/availabilities/spaces.json.jbuilder
+++ b/app/views/api/availabilities/spaces.json.jbuilder
@@ -19,8 +19,8 @@ json.array!(@slots) do |slot|
   # the user who booked the slot, if the slot was reserved
   if (%w[admin manager].include? @current_user_role) && slot.reservation
     json.user do
-      json.id slot.reservation.user.id
-      json.name slot.reservation.user.profile.full_name
+      json.id slot.reservation.user&.id
+      json.name slot.reservation.user&.profile&.full_name
     end
   end
   json.tag_ids slot.availability.tag_ids
diff --git a/app/views/api/reservations/_reservation.json.jbuilder b/app/views/api/reservations/_reservation.json.jbuilder
index b2be48b4b..402fb765d 100644
--- a/app/views/api/reservations/_reservation.json.jbuilder
+++ b/app/views/api/reservations/_reservation.json.jbuilder
@@ -2,7 +2,7 @@
 
 json.id reservation.id
 json.user_id reservation.statistic_profile.user_id
-json.user_full_name reservation.user.profile.full_name
+json.user_full_name reservation.user&.profile&.full_name
 json.message reservation.message
 json.slots_attributes reservation.slots do |s|
   json.id s.id
diff --git a/config/locales/app.admin.de.yml b/config/locales/app.admin.de.yml
index 413b5e61f..73bd82fef 100644
--- a/config/locales/app.admin.de.yml
+++ b/config/locales/app.admin.de.yml
@@ -109,6 +109,7 @@ de:
         slots: "Slots"
         slots_of: "von"
         minutes: "Minuten"
+        deleted_user: "Deleted user"
       #import external iCal calendar
       icalendar:
         icalendar_import: "iCalendar Import"
@@ -508,6 +509,7 @@ de:
         important_notes: "Wichtige Hinweise"
         address_and_legal_information: "Adresse und rechtliche Informationen"
         invoice_reference: "Rechnungsbezug"
+        invoice_reference_is_required: "Invoice reference is required."
         text: "Text"
         year: "Jahr"
         month: "Monat"
diff --git a/config/locales/app.admin.en.yml b/config/locales/app.admin.en.yml
index f2e58f01d..e4cc9de5a 100644
--- a/config/locales/app.admin.en.yml
+++ b/config/locales/app.admin.en.yml
@@ -109,6 +109,7 @@ en:
         slots: "slots"
         slots_of: "of"
         minutes: "minutes"
+        deleted_user: "Deleted user"
       # import external iCal calendar
       icalendar:
         icalendar_import: "iCalendar import"
@@ -508,6 +509,7 @@ en:
         important_notes: "Important notes"
         address_and_legal_information: "Address and legal information"
         invoice_reference: "Invoice reference"
+        invoice_reference_is_required: "Invoice reference is required."
         text: "text"
         year: "Year"
         month: "Month"
diff --git a/config/locales/app.admin.es.yml b/config/locales/app.admin.es.yml
index 995b97e9b..5d87d0d5e 100644
--- a/config/locales/app.admin.es.yml
+++ b/config/locales/app.admin.es.yml
@@ -109,6 +109,7 @@ es:
         slots: "slots"
         slots_of: "of"
         minutes: "minutes"
+        deleted_user: "Deleted user"
       #import external iCal calendar
       icalendar:
         icalendar_import: "iCalendar import"
@@ -508,6 +509,7 @@ es:
         important_notes: "Notas importantes"
         address_and_legal_information: "Dirección e información legal"
         invoice_reference: "Referencia de factura"
+        invoice_reference_is_required: "Invoice reference is required."
         text: "text"
         year: "Año"
         month: "Mes"
diff --git a/config/locales/app.admin.fr.yml b/config/locales/app.admin.fr.yml
index 0185b4aff..47de2256d 100644
--- a/config/locales/app.admin.fr.yml
+++ b/config/locales/app.admin.fr.yml
@@ -109,6 +109,7 @@ fr:
         slots: "créneaux"
         slots_of: "de"
         minutes: "minutes"
+        deleted_user: "Utilisateur supprimé"
       #import external iCal calendar
       icalendar:
         icalendar_import: "Import iCalendar"
@@ -508,6 +509,7 @@ fr:
         important_notes: "Informations importantes"
         address_and_legal_information: "Adresse et informations légales"
         invoice_reference: "Référence facture"
+        invoice_reference_is_required: "La référence facture est requis."
         text: "texte"
         year: "Année"
         month: "Mois"
diff --git a/config/locales/app.admin.no.yml b/config/locales/app.admin.no.yml
index 672626240..a2f390b65 100644
--- a/config/locales/app.admin.no.yml
+++ b/config/locales/app.admin.no.yml
@@ -109,6 +109,7 @@
         slots: "reservasjoner"
         slots_of: "av"
         minutes: "minutter"
+        deleted_user: "Deleted user"
       #import external iCal calendar
       icalendar:
         icalendar_import: "iCalendar import"
@@ -508,6 +509,7 @@
         important_notes: "Viktige merknader"
         address_and_legal_information: "Adresse og juridisk informasjon"
         invoice_reference: "Fakturareferanse"
+        invoice_reference_is_required: "Invoice reference is required."
         text: "tekst"
         year: "År"
         month: "Måned"
diff --git a/config/locales/app.admin.pt.yml b/config/locales/app.admin.pt.yml
index dfa8991af..9ef64f1d7 100755
--- a/config/locales/app.admin.pt.yml
+++ b/config/locales/app.admin.pt.yml
@@ -109,6 +109,7 @@ pt:
         slots: "slots"
         slots_of: "do"
         minutes: "minutos"
+        deleted_user: "Deleted user"
       #import external iCal calendar
       icalendar:
         icalendar_import: "importar iCalendar"
@@ -508,6 +509,7 @@ pt:
         important_notes: "Notas importantes"
         address_and_legal_information: "Endereço e informações legais"
         invoice_reference: "Referencia de fatura"
+        invoice_reference_is_required: "Invoice reference is required."
         text: "texto"
         year: "Ano"
         month: "Mês"
diff --git a/config/locales/app.admin.zu.yml b/config/locales/app.admin.zu.yml
index 1641ab695..d95f24c31 100644
--- a/config/locales/app.admin.zu.yml
+++ b/config/locales/app.admin.zu.yml
@@ -109,6 +109,7 @@ zu:
         slots: "crwdns20302:0crwdne20302:0"
         slots_of: "crwdns20304:0crwdne20304:0"
         minutes: "crwdns20288:0crwdne20288:0"
+        deleted_user: "Deleted user"
       #import external iCal calendar
       icalendar:
         icalendar_import: "crwdns6855:0crwdne6855:0"
@@ -508,6 +509,7 @@ zu:
         important_notes: "crwdns7385:0crwdne7385:0"
         address_and_legal_information: "crwdns7387:0crwdne7387:0"
         invoice_reference: "crwdns7389:0crwdne7389:0"
+        invoice_reference_is_required: "Invoice reference is required."
         text: "crwdns21060:0crwdne21060:0"
         year: "crwdns7391:0crwdne7391:0"
         month: "crwdns7393:0crwdne7393:0"
diff --git a/config/locales/app.shared.de.yml b/config/locales/app.shared.de.yml
index 5690b9b2f..c6c5c9b1c 100644
--- a/config/locales/app.shared.de.yml
+++ b/config/locales/app.shared.de.yml
@@ -283,6 +283,7 @@ de:
         do_you_want_to_change_NAME_s_booking_slot_initially_planned_at: "Möchten Sie den {NAME}-Buchungsplatz ändern? Ursprünglich geplant um:"
         cancel_this_reservation: "Reservierung stornieren"
         i_want_to_change_date: "Ich möchte das Datum ändern"
+        deleted_user: "Deleted user"
       #user public profile
       public_profile:
         last_activity_html: "Letzte Aktivität <br><strong>am {DATE}</strong>"
diff --git a/config/locales/app.shared.en.yml b/config/locales/app.shared.en.yml
index 6f647d6fc..b7f029d88 100644
--- a/config/locales/app.shared.en.yml
+++ b/config/locales/app.shared.en.yml
@@ -283,6 +283,7 @@ en:
         do_you_want_to_change_NAME_s_booking_slot_initially_planned_at: "Do you want to change {NAME}'s booking slot, initially planned at:"
         cancel_this_reservation: "Cancel this reservation"
         i_want_to_change_date: "I want to change date"
+        deleted_user: "deleted user"
       #user public profile
       public_profile:
         last_activity_html: "Last activity <br><strong>on {DATE}</strong>"
diff --git a/config/locales/app.shared.es.yml b/config/locales/app.shared.es.yml
index 692915093..e1212c6bb 100644
--- a/config/locales/app.shared.es.yml
+++ b/config/locales/app.shared.es.yml
@@ -283,6 +283,7 @@ es:
         do_you_want_to_change_NAME_s_booking_slot_initially_planned_at: "Desea cambiar la reserva de {NAME} , efectuada inicialmente el:"
         cancel_this_reservation: "Cancelar reserva"
         i_want_to_change_date: "Quiero cambiar la fecha"
+        deleted_user: "deleted user"
       #user public profile
       public_profile:
         last_activity_html: "Last activity <br><strong>on {DATE}</strong>"
diff --git a/config/locales/app.shared.fr.yml b/config/locales/app.shared.fr.yml
index 4ddfca19f..2247bef6f 100644
--- a/config/locales/app.shared.fr.yml
+++ b/config/locales/app.shared.fr.yml
@@ -283,6 +283,7 @@ fr:
         do_you_want_to_change_NAME_s_booking_slot_initially_planned_at: "Souhaitez-vous changer le créneau de réservation de {NAME}, initialement prévu au :"
         cancel_this_reservation: "Annuler cette réservation"
         i_want_to_change_date: "Je veux changer de date"
+        deleted_user: "l'utilisateur supprimé"
       #user public profile
       public_profile:
         last_activity_html: "Dernière activité <br><strong>le {DATE}</strong>"
diff --git a/config/locales/app.shared.no.yml b/config/locales/app.shared.no.yml
index b241457f0..5076413cd 100644
--- a/config/locales/app.shared.no.yml
+++ b/config/locales/app.shared.no.yml
@@ -283,6 +283,7 @@
         do_you_want_to_change_NAME_s_booking_slot_initially_planned_at: "Vil du endre {NAME} sin bestillingsplass, som opprinnelig er planlagt på:"
         cancel_this_reservation: "Avbryt reservasjon"
         i_want_to_change_date: "Jeg vil endre dato"
+        deleted_user: "deleted user"
       #user public profile
       public_profile:
         last_activity_html: "Siste aktivitet <br><strong>{DATE}</strong>"
diff --git a/config/locales/app.shared.pt.yml b/config/locales/app.shared.pt.yml
index 2e85e3b1a..1979341cb 100755
--- a/config/locales/app.shared.pt.yml
+++ b/config/locales/app.shared.pt.yml
@@ -283,6 +283,7 @@ pt:
         do_you_want_to_change_NAME_s_booking_slot_initially_planned_at: "Você deseja alterar o agendamento do usuário {NAME}, inicialmente marcado para:"
         cancel_this_reservation: "Cancelar essa reserva"
         i_want_to_change_date: "Eu quero alterar a data"
+        deleted_user: "deleted user"
       #user public profile
       public_profile:
         last_activity_html: "Última atividade <br><strong>em {DATE}</strong>"
diff --git a/config/locales/app.shared.zu.yml b/config/locales/app.shared.zu.yml
index b5bb13608..bdfd31a34 100644
--- a/config/locales/app.shared.zu.yml
+++ b/config/locales/app.shared.zu.yml
@@ -283,6 +283,7 @@ zu:
         do_you_want_to_change_NAME_s_booking_slot_initially_planned_at: "crwdns9825:0{NAME}crwdne9825:0"
         cancel_this_reservation: "crwdns9827:0crwdne9827:0"
         i_want_to_change_date: "crwdns9829:0crwdne9829:0"
+        deleted_user: "deleted user"
       #user public profile
       public_profile:
         last_activity_html: "crwdns9843:0{DATE}crwdne9843:0"
diff --git a/config/locales/de.yml b/config/locales/de.yml
index 47c7bf63f..d082224cc 100644
--- a/config/locales/de.yml
+++ b/config/locales/de.yml
@@ -53,6 +53,7 @@ de:
     i_ve_reserved: "Ich reservierte"
     length_must_be_slot_multiple: "muss mindestens %{MIN} Minuten nach dem Startdatum liegen"
     must_be_associated_with_at_least_1_machine: "muss mindestens einer Maschine zugeordnet sein"
+    deleted_user: "Deleted user"
   #members management
   members:
     unable_to_change_the_group_while_a_subscription_is_running: "Die Gruppe kann während eines Abonnements nicht geändert werden"
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 4ad225bab..be7505591 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -53,6 +53,7 @@ en:
     i_ve_reserved: "I've reserved"
     length_must_be_slot_multiple: "must be at least %{MIN} minutes after the start date"
     must_be_associated_with_at_least_1_machine: "must be associated with at least 1 machine"
+    deleted_user: "Deleted user"
   #members management
   members:
     unable_to_change_the_group_while_a_subscription_is_running: "Unable to change the group while a subscription is running"
diff --git a/config/locales/es.yml b/config/locales/es.yml
index 4df65c2b5..27bd12a91 100644
--- a/config/locales/es.yml
+++ b/config/locales/es.yml
@@ -53,6 +53,7 @@ es:
     i_ve_reserved: "He reservado"
     length_must_be_slot_multiple: "Debe ser al menos %{MIN} minutos después de la fecha de inicio"
     must_be_associated_with_at_least_1_machine: "debe estar asociado con al menos 1 máquina"
+    deleted_user: "Deleted user"
   #members management
   members:
     unable_to_change_the_group_while_a_subscription_is_running: "No se puede cambiar de grupo mientras haya una suscripción en curso"
diff --git a/config/locales/fr.yml b/config/locales/fr.yml
index 18392c278..3c01a72b6 100644
--- a/config/locales/fr.yml
+++ b/config/locales/fr.yml
@@ -53,6 +53,7 @@ fr:
     i_ve_reserved: "J'ai réservé"
     length_must_be_slot_multiple: "doit être au moins %{MIN} minutes après la date de début"
     must_be_associated_with_at_least_1_machine: "doit être associé avec au moins 1 machine"
+    deleted_user: "Utilisateur supprimé"
   #members management
   members:
     unable_to_change_the_group_while_a_subscription_is_running: "Impossible de changer le groupe tant qu'un abonnement est en cours"
diff --git a/config/locales/no.yml b/config/locales/no.yml
index 404366f3f..0e2e2a515 100644
--- a/config/locales/no.yml
+++ b/config/locales/no.yml
@@ -53,6 +53,7 @@
     i_ve_reserved: "Jeg har reservert"
     length_must_be_slot_multiple: "må være minst %{MIN} minutter etter startdatoen"
     must_be_associated_with_at_least_1_machine: "må være tilknyttet minst 1 maskin"
+    deleted_user: "Deleted user"
   #members management
   members:
     unable_to_change_the_group_while_a_subscription_is_running: "Kan ikke endre gruppen mens et abonnement kjører"
diff --git a/config/locales/pt.yml b/config/locales/pt.yml
index b0300eb88..be8fc3acc 100755
--- a/config/locales/pt.yml
+++ b/config/locales/pt.yml
@@ -53,6 +53,7 @@ pt:
     i_ve_reserved: "Eu reservei"
     length_must_be_slot_multiple: "deve ser pelo menos %{MIN} minutos após a data de início"
     must_be_associated_with_at_least_1_machine: "deve estar associada a pelo menos uma máquina"
+    deleted_user: "Deleted user"
   #members management
   members:
     unable_to_change_the_group_while_a_subscription_is_running: "Não é possível alterar o grupo enquanto uma assinatura está sendo executada"
diff --git a/config/locales/zu.yml b/config/locales/zu.yml
index d798bef18..e4a426e88 100644
--- a/config/locales/zu.yml
+++ b/config/locales/zu.yml
@@ -53,6 +53,7 @@ zu:
     i_ve_reserved: "crwdns3269:0crwdne3269:0"
     length_must_be_slot_multiple: "crwdns3271:0%{MIN}crwdne3271:0"
     must_be_associated_with_at_least_1_machine: "crwdns3273:0crwdne3273:0"
+    deleted_user: "Deleted user"
   #members management
   members:
     unable_to_change_the_group_while_a_subscription_is_running: "crwdns3275:0crwdne3275:0"
diff --git a/lib/stripe/service.rb b/lib/stripe/service.rb
index 3da2035be..d3536f646 100644
--- a/lib/stripe/service.rb
+++ b/lib/stripe/service.rb
@@ -120,6 +120,8 @@ class Stripe::Service < Payment::Service
       pgo = PaymentGatewayObject.find_or_initialize_by(item: payment_schedule_item)
       pgo.gateway_object = stp_invoice
       pgo.save!
+    elsif stp_invoice.status == 'draft'
+      return # Could be that the stripe invoice does not yet reflect the payment made by the member, because we called that service just after payment is made. We call return here and PaymentScheduleItemWorker will anyway call that method every hour
     else
       notify_payment_schedule_item_error(payment_schedule_item)
       payment_schedule_item.update_attributes(state: 'error')
diff --git a/lib/tasks/fablab/maintenance.rake b/lib/tasks/fablab/maintenance.rake
index 47bd64bc5..0fde17d13 100644
--- a/lib/tasks/fablab/maintenance.rake
+++ b/lib/tasks/fablab/maintenance.rake
@@ -126,5 +126,19 @@ namespace :fablab do
       )
       puts '-> Done'
     end
+
+    desc 'Regenerate the invoices (invoices & avoirs) reference'
+    task :regenerate_invoices_reference, %i[year month] => :environment do |_task, args|
+      year = args.year || Time.current.year
+      month = args.month || Time.current.month
+      start_date = Time.zone.local(year.to_i, month.to_i, 1)
+      end_date = start_date.next_month
+      puts "-> Start regenerate the invoices reference between #{I18n.l start_date, format: :long} and " \
+         "#{I18n.l end_date - 1.minute, format: :long}"
+      invoices = Invoice.where('created_at >= :start_date AND created_at < :end_date', start_date: start_date, end_date: end_date)
+                        .order(created_at: :asc)
+      invoices.each(&:update_reference)
+      puts '-> Done'
+    end
   end
 end
diff --git a/package.json b/package.json
index 774cf2f8d..a9fccb548 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "fab-manager",
-  "version": "5.3.9",
+  "version": "5.3.10",
   "description": "Fab-manager is the FabLab management solution. It provides a comprehensive, web-based, open-source tool to simplify your administrative tasks and your marker's projects.",
   "keywords": [
     "fablab",