On my old phone I had an issue with the proximity sensor and front facing camera. This led me to holding my phone backwards to take photos and being unable to hang up phone calls.
I think I put up with this for a year and a half.
I did end up figuring out the issue with the proximity sensor but opening up my phone to reconnect the camera module was too much effort for me.
My iPhone 4S went for a swim before phones were generally waterproof and the screen backlight went out and the camera light stayed permanently on. I used the blind assist mode with the phone for a few months and even took photos totally blind. Eventually the backlight came on again and I could use the phone totally normal. Finally killed it falling out of my pocket 150’ up while rock climbing. Great phone though.