diff --git a/CHANGELOG.md b/CHANGELOG.md
index 62d901b08..0d4bda6fd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@
 - Fix a bug: changing the date of a training session does not prevent the selection of a different type of training
 - Fix a bug: unable to change the date formats using the setup script
 - Fix a bug: missing translation for projets drafts in public profile
+- Fix a bug: email notification after reservation update have wrong previous date (#234)
 - Updated contribution guidelines
 - Updated summernote to 0.8.18
 - Updated angular-summernote to 0.8.1
diff --git a/app/models/slot.rb b/app/models/slot.rb
index 3af13f833..20f458be5 100644
--- a/app/models/slot.rb
+++ b/app/models/slot.rb
@@ -62,7 +62,7 @@ class Slot < ApplicationRecord
   end
 
   def set_ex_start_end_dates_attrs
-    update_columns(ex_start_at: start_at_was, ex_end_at: end_at_was)
+    update_columns(ex_start_at: start_at_before_last_save, ex_end_at: end_at_before_last_save)
   end
 
   def update_event_nb_free_places