diff --git a/trytond/model/modelsql.py b/trytond/model/modelsql.py
index f5320e3530..3cb79f5060 100644
--- a/trytond/model/modelsql.py
+++ b/trytond/model/modelsql.py
@@ -1047,7 +1047,8 @@ class ModelSQL(ModelStorage):
                 if rowcount == -1 or rowcount is None:
                     rowcount = len(cursor.fetchall())
                 if not rowcount == len({}.fromkeys(sub_ids)):
-                    cls.raise_user_error('access_error', cls._description)
+                    cls.raise_user_error('access_error',
+                        cls.__doc__.splitlines()[0])
 
         cls.trigger_delete(records)