diff --git a/CHANGELOG.md b/CHANGELOG.md
index 94a9c2d4b..5115e3b45 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,7 @@
 - Removed dependency to auto-ngtemplate-loader
 - Removed support for Universal Analytics
 - Updated deprecated division operators in sass
+- Fix a bug: prepaid-packs purchases are reported as subscriptions in the statistics
 - Fix a bug: error Couldn't find the binary git during assets compilation
 - Fix a bug: a sentence was not linked to a translation key
 - Fix a bug: the version check may be scheduled at an invalid time
@@ -30,6 +31,7 @@
 - Fix a security issue: updated puma to 4.3.11 to fix [CVE-2022-23634](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-23634)
 - Fix a security issue: updated i18next-http-backend to 1.3.2 to fix [CVE-2022-0235](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-0235)
 - Fix a security issue: updated follow-redirects to 1.18.8 to fix [CVE-2022-0536](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-0536)
+- [TODO DEPLOY] `rails fablab:maintenance:regenerate_statistics[2021,07]`
 - [TODO DEPLOY] `\curl -sSL https://raw.githubusercontent.com/sleede/fab-manager/master/scripts/cve-2021-44228.sh | bash`
 - [TODO DEPLOY] migrate your Google Analytics property to GA4, see [this guide](https://support.google.com/analytics/answer/9744165)
 - [TODO DEPLOY] update your tracking ID in Customization > Privacy > Statistics > Google Analytics
diff --git a/app/models/invoice_item.rb b/app/models/invoice_item.rb
index 9d8cfe867..c9738ec8a 100644
--- a/app/models/invoice_item.rb
+++ b/app/models/invoice_item.rb
@@ -8,11 +8,6 @@ class InvoiceItem < Footprintable
   has_one :payment_gateway_object, as: :item
 
   belongs_to :object, polymorphic: true
-  belongs_to :reservation, foreign_type: 'Reservation', foreign_key: 'object_id'
-  belongs_to :subscription, foreign_type: 'Subscription', foreign_key: 'object_id'
-  belongs_to :wallet_transaction, foreign_type: 'WalletTransaction', foreign_key: 'object_id'
-  belongs_to :offer_day, foreign_type: 'OfferDay', foreign_key: 'object_id'
-  belongs_to :statistic_profile_prepaid_pack, foreign_type: 'StatisticProfilePrepaidPack', foreign_key: 'object_id'
 
   after_create :chain_record
   after_update :log_changes
diff --git a/app/pdfs/pdf/invoice.rb b/app/pdfs/pdf/invoice.rb
index 8036951b8..d0efe9aa8 100644
--- a/app/pdfs/pdf/invoice.rb
+++ b/app/pdfs/pdf/invoice.rb
@@ -97,9 +97,9 @@ class PDF::Invoice < Prawn::Document
                           DATE: I18n.l(invoice.main_item.object.slots[0].start_at.to_date),
                           TIME: I18n.l(invoice.main_item.object.slots[0].start_at, format: :hour_minute))
           invoice.invoice_items.each do |item|
-            next unless item.subscription
+            next unless item.object_type == Subscription.name
 
-            subscription = item.subscription
+            subscription = item.object
             cancellation = invoice.is_a?(Avoir) ? I18n.t('invoices.cancellation') + ' - ' : ''
             object = "\n- #{object}\n- #{cancellation + subscription_verbose(subscription, name)}"
             break
@@ -135,7 +135,7 @@ class PDF::Invoice < Prawn::Document
         details = invoice.is_a?(Avoir) ? I18n.t('invoices.cancellation') + ' - ' : ''
 
         if item.object_type == Subscription.name
-          subscription = item.subscription
+          subscription = item.object
           if invoice.main_item.object_type == 'OfferDay'
             details += I18n.t('invoices.subscription_extended_for_free_from_START_to_END',
                               START: I18n.l(invoice.main_item.object.start_at.to_date),
diff --git a/app/services/statistic_service.rb b/app/services/statistic_service.rb
index 3ccfb1097..37965049d 100644
--- a/app/services/statistic_service.rb
+++ b/app/services/statistic_service.rb
@@ -129,10 +129,13 @@ class StatisticService
     InvoiceItem.where('invoice_items.created_at >= :start_date AND invoice_items.created_at <= :end_date', options)
                .eager_load(invoice: [:coupon], subscription: [:plan, statistic_profile: [:group]]).each do |i|
       next if i.invoice.is_a?(Avoir)
+      next unless i.invoice_item_type == Subscription.name
 
-      sub = i.subscription
-
-      next unless sub
+      sub = if i.object_type == Subscription.name
+              i.object
+            else
+              i.object.subscription
+            end
 
       ca = i.amount.to_i
       cs = CouponService.new
diff --git a/test/integration/reservations/create_as_admin_test.rb b/test/integration/reservations/create_as_admin_test.rb
index 0af1e4a68..a4421dfcd 100644
--- a/test/integration/reservations/create_as_admin_test.rb
+++ b/test/integration/reservations/create_as_admin_test.rb
@@ -499,7 +499,7 @@ class Reservations::CreateAsAdminTest < ActionDispatch::IntegrationTest
     # invoice_items
     invoice_items = InvoiceItem.last(2)
 
-    assert(invoice_items.any? { |ii| ii.amount == plan.amount && !ii.subscription.nil? })
+    assert(invoice_items.any? { |ii| ii.amount == plan.amount && ii.object_type == Subscription.name })
     assert(invoice_items.any? { |ii| ii.amount.zero? })
 
     # invoice assertions
diff --git a/test/integration/reservations/create_test.rb b/test/integration/reservations/create_test.rb
index 415b9799b..6aea7ab1f 100644
--- a/test/integration/reservations/create_test.rb
+++ b/test/integration/reservations/create_test.rb
@@ -622,7 +622,7 @@ class Reservations::CreateTest < ActionDispatch::IntegrationTest
 
     assert_not_nil subscription_item
 
-    subscription = subscription_item.subscription
+    subscription = subscription_item.object
 
     assert_equal subscription_item.amount, plan.amount
     assert_equal subscription.plan_id, plan.id