Proximity sensor not working after display replacement
I had a broken screen so I ordered a new display with home button, front camera and proximity sensor already assembled in the display frame.
I replaced the display and all works fine except the proximity sensor. Actually, if I press my thumb hard against the proximity sensor area, it works after a 2 seconds lag or so.
What can be the cause and how to fix? My iPhone 5 if black.
Is this a good question?