Front camera not working on third party apps after screen replacement.

Okay guys so I had just had my screen fixed , it was a full assembly when replaced. My front and back camera works perfect on my regular camera. But as soon as I FaceTime or video call the front camera is completely black but the back camera is fine. It does the same when I try to use the front camera on Facebook, messenger, or instagram. It automatically closes my Snapchat out due to it being on my front camera when I open it. I’ve tried resetting settings, restarting my phone, and deleting and reinstalling my apps. But I don’t think it could be anything with the proximity sensor because like I stated it works perfectly fine on my regular camera. I’ve searched and asked for the answer everywhere possible on why it is doing that and I’m having no luck! Does anyone know why it could be doing it? How do I fix it?