Making Mtn. Plant Mandatory for Notifications

Hi PM Gurus,

I created a PM Notification Type where the Maintenance Plant comes in second tab (Location Tab). Also this field is made mandatory (required entry). But when users created a notification, system allows save with out an enty to Maintenance Plant field. It s only prompted if the user clicks the second tab (Locations Tab). Is there a way to resolve this issue so that system doesn't allow users to save notifications even if they dont click Locations tab.

Cheers

Deepal