****Solution****
So my Face ID out of the blue stopped working. I have no idea why… weird glitch. My phone wouldn’t recognize my face at all. I followed all the steps recommended (turn Face ID off, create alt appearance, reset face id, software update, factory reset, etc) to no avail. I just assumed the hardware dealing with the Face ID failed internally and I was SOL. Weeks later I FINALLY have found the solution.
Bizarre that this is linked somehow but I went into settings and turned off iMessage and FaceTime. I reenabled both and noticed that my Apple ID wasn’t linked to either one. I linked my Apple ID to both FaceTime and iMessage and Wa-La…. My Face ID started working again. Hope this helps someone!