Chosen Solution
So I just did a screen replacement and my Face ID and everything else was working fine when it suddenly stopped so I opened it up and found the ear piece assembly has a slightly torn flex cable I’m not sure what to do The image below is pretty bad quality but where I’m pointing is the corner that is slightly torn
Ouch, I’m afraid that’s bad. The front sensor assembly is paired to the motherboard and only Apple can do that pairing, which means you could replace it but Face ID will not work with the new part. You’d have to take it to Apple for the repair in order to replace the assembly and keep your Face ID. The only other option I’ve seen is the possibility that a repair shop might be able to replace that flex cable for you; unsoldering it from the components and replacing it with an intact cable. That takes specialized equipment and skills, so not just anyone can do it; I consider myself a fairly expert home repairman, but that’s one I wouldn’t even try to tackle myself. If you post your location (country, region/state/province, and maybe city - whatever you’re comfortable with), you might get some suggestions for repair shops that can handle that repair. Otherwise, Google may be your best friend to locate a repair facility.
