We have a Vizio 64in that did the EXACT same thing after about a year of use.
We gave up, put it into the box and in the garage it went.
I was cleaning the garage and asked my husband if I could get it out of there but then couldn’t bring myself to just pitch it and so I started reading...
Set it back to factory settings.
About 8 mos ago we did that and it’s going great.
Oh and https://support.vizio.com/s/article/Restoring-Factory-Defaults-on-VIZIO-TV?language=en_US
Doesn’t cost anything to try. :)