diff --git a/app/services/base_type_service.rb b/app/services/base_type_service.rb
index b554931382..6109c11a29 100644
--- a/app/services/base_type_service.rb
+++ b/app/services/base_type_service.rb
@@ -79,6 +79,6 @@ class BaseTypeService
       end
     end
 
-    type.custom_field_ids = active_cf_ids
+    type.custom_field_ids = active_cf_ids.uniq
   end
 end