It is helpful to download the apple support app. That way you can make an appointment through the app, and only need to show your ID at the store.
Yes the genius bar
Replace CAMERA!
First to test if it is software or hardware. Update to The Latest Version 11.2 Then Do full restore by using iTunes. If it is happen then it might be a hardware, therefore take it to Genius Bar to get it fix. Second option, take to local repair shop.
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