Clean Your iPhone
Try is cleaning the notch (the black cutout at the top of your iPhone’s screen) and see if that fixes the problem. Sometimes it’s possible that something as little as a speck of dust might be covering your device’s TrueDepth camera!
You should try cleaning your iPhone or iPad with a soft, slightly damp microfiber cloth. Clean the notch softly until you’re sure you removed the residue covering the TrueDepth camera.