Oracle Form is saving without entering data in the mandatory field

 Hi ,There was a requirement for us to make a supplier lot number field mandatory which is available in the Details Tab of the Receipts Window.

This field should be made mandatory only when we receive against a PO whose line Item should be lot controlled.

Navigation:

Purchasing Super User --> Receiving--> Receipts

I wrote the required condition and the field is made mandatory that is suppose if there are 2 lines in a PO and one line is having item which is lot enabled and the other is not enabled then the line which is lot enabled is only made mandatory.