SIT userhooks validation not working at the time of request submission

Hi All,

We are working on oracle HRMS. Our application version is  12.1.2.

I need to perform some database validation for SIT.

So created a custom package to validate the data. i registerd this package in user hook.

hook name

 HR_SIT_BK1.CREATE_SIT_B

Hook type

BP.

This SIT userhooks validation not working at the time of request submission but they are executed at the time of final approval.

but i need this validation at the time of Submission. Please help me how i can achive this.

Thanks

Arumugam