I read someone's fix to this, it said it could be a conflicting input or remote from for example a fire stick. He said to take out batteries from other remote( the batteries might be low on either remote). It sounded a little ridiculous. But it worked for me. I'm still not sold but it kept me from doing a factory re+boot and then trying to find passwords from three years ago that I have no way of finding.
So take batteries out of other remotes connected to your TV. And remember to always pray to Satan he can kick Jesus'