diff --git a/app/models/concerns/active_admin_multi_upload/uploadable.rb b/app/models/concerns/active_admin_multi_upload/uploadable.rb
index f648800..a83a11e 100644
--- a/app/models/concerns/active_admin_multi_upload/uploadable.rb
+++ b/app/models/concerns/active_admin_multi_upload/uploadable.rb
@@ -20,7 +20,7 @@ def to_jq_upload
           }
         end
       eoruby
-      class_eval(code)
+      class_eval(code) unless self.instance_methods.include? :to_jq_upload
     end
   end
 end