diff --git a/app/models/module_app.rb b/app/models/module_app.rb
index ef249a0b..a177f23f 100644
--- a/app/models/module_app.rb
+++ b/app/models/module_app.rb
@@ -46,7 +46,7 @@ class ModuleApp
   def assign_manager(user,assigner)
     manager = AppManager.first(conditions: {managing_app_id: self.id,user_id: user.id}) rescue nil    
     if manager.nil? 
-      manager = self.managers.create(:user => user,:rule_creator => assigner)
+      manager = self.managers.create(:user_id => user.id,:rule_creator_id => (assigner.id rescue nil))
     end
     manager
   end
@@ -54,7 +54,7 @@ class ModuleApp
   def assign_sub_manager(user,assigner)
     submanager = AppManager.first(conditions: {sub_managing_app_id: self.id,user_id: user.id}) rescue nil
     if submanager.nil? && !self.managing_users.include?(user)
-      submanager = self.sub_managers.create(:user_id => user.id,:rule_creator_id => assigner.id)
+      submanager = self.sub_managers.create(:user_id => user.id,:rule_creator_id => (assigner.id rescue nil) )
     end
     submanager
   end