Warning pop-up not showing with back arrow

Hey guys,

I build an estimate application for our collision center and while on the form, some of our employees are used to press the back arrow on other apps, however, when they do in app sheet, the estimate deletes itself with a warning. Is there a behavior I can add to at least show a message?

Worst case can I hide the arrow when filling out a form ?

Here is a video :
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