Re: [FULL] ONE UI 3 ANDROID 11 UPDATE!!! [S20 ULTRA]
Give this a try. Settings, About, Software and keep tapping the "Carrier Configuration Version" repeatedly and hit update. Do not minimize the app until it's complete turn the phone on and off (even if it says "fail try again")!!!
Then do a "Cache Partition Clean" from the Bootloader screen.
best of luck to you, I know you will get it trust me!!!