diff --git a/CHANGELOG.md b/CHANGELOG.md
index 80bd4367b..976a376c0 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,7 @@
 - Fix a bug: invalid link to the user's manual
 - Fix a bug: unable to sync coupons on stripe
 - Fix a bug: ignored coupon when booking an event with card payment
+- Fix a bug: deleting a coupon displays an error message
 
 ## v5.0.4 2021 June 15
 
diff --git a/app/models/coupon.rb b/app/models/coupon.rb
index 235997423..744ad35ba 100644
--- a/app/models/coupon.rb
+++ b/app/models/coupon.rb
@@ -6,7 +6,7 @@ class Coupon < ApplicationRecord
   has_many :payment_schedule
 
   after_create :create_gateway_coupon
-  after_commit :delete_gateway_coupon, on: [:destroy]
+  before_destroy :delete_gateway_coupon
 
   validates :name, presence: true
   validates :code, presence: true
diff --git a/config/routes.rb b/config/routes.rb
index a5614461c..826887a0b 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -78,9 +78,10 @@ Rails.application.routes.draw do
     resources :prices, only: %i[index update] do
       post 'compute', on: :collection
     end
-    resources :coupons
-    post 'coupons/validate' => 'coupons#validate'
-    post 'coupons/send' => 'coupons#send_to'
+    resources :coupons do
+      post 'validate', action: 'validate', on: :collection
+      post 'send', action: 'send_to', on: :collection
+    end
 
     resources :trainings_pricings, only: %i[index update]