EBS 12.2 form personalisation , Supervisior field is mandatory but still am able to save the records

Question

I made the supervisor field in Assignment screen mandatory by form personalisation but when i save the records without entering data in Supervisor field it allows me to save the record.

FORM PERSONALISATION parameters
Trigger Event :- WHEN-NEW-FORM-INSTANCE
Processing Mode :- NOT-IN-ENTER-QUERY-MODE
ACTION
SEQ :- 10
TYPE :- PROPERTY
LANGUAGE :- ALL
OBJECT TYPE :- ITEM
TARGET OBJECT :- ASSGT.SUPERVISOR_NAME
PROPERTY NAME :- REQUIRED
VALUE :- TRUE