Hmm. I keep scratching around for a solution for this. I've F.A. faith in samsung. S21 ultra for me. Bought brand new in January 2024 from ebay. As far as I know it's genuine. Came shrink wrapped.
It was an import though and snapdragon. Xaa region code (unlocked usa). No idea if any of this is relevant.
One ui 6.1 took out the screen on June 23rd. Works with a spen, but it may as well be a brick.
Tried the odin stuff, but got nowhere with that because the bootloader is fused to 13, and the rollback option binary was v10. So, I'm screwed.
I'm not sure when the bootloader changed as I've installed every update since.
If you've just discovered your screen is dead, don't install anymore updates until you try and rollback to 6.0
