diff --git a/app/models/cost_object.rb b/app/models/cost_object.rb
index cc813f7505..3d59dd0f32 100644
--- a/app/models/cost_object.rb
+++ b/app/models/cost_object.rb
@@ -29,8 +29,7 @@ class CostObject < ActiveRecord::Base
 
   include ActiveModel::ForbiddenAttributesProtection
 
-  acts_as_attachable after_remove: :attachment_removed
-
+  acts_as_attachable
   acts_as_journalized
 
   acts_as_event type: 'cost-objects',