How do I make the ID number (Q0002-PERID) optional

I went to PA30 and found via F1 + F9 the following:

Program Name = MP000200

Sreen Number = 2044

Then I went to SPRO

- Personnel Management

- Personnel Administration

- Customizing User Interfaces

- Change Screen Modifications

BUT there is no entry for Module Pool Name = MP000200 for Screen = 2044.

Where should I look then?