iPhone XR screen suddenly went gray, photo negative, screen burned
I was using my iPhone XR last night (just watching Instagram stories) and suddenly my screen flashed gray. Closed out the app and everything on my screen was grayscale, looked like a photo negative, and showed screen burn throughout the screen. It has been 12+ hours with no resolution. I checked all the accessibility features listed in the support articles (inverted colors, etc) and nothing fixed the problem. Adjusted literally every display option but nothing worked. Restarted phone multiple times and nothing. Reset my phone settings, and still nothing. Finally did a complete factory reset and that still didn't solve the problem. I have searched for anything to indicate that someone else has had this problem but nada; seems like people get stuck with inverted colors or in grayscale, but not this weird issue. You can see from the photo that there is screen burn from multiple previous things that have been opened. Any clue what on earth caused this or how to fix it?
iPhone XR