I found a way to fix it. You have to go into the switchs Data and actually delete all the save data.
Everything was working fine for me this morning, then about 1 PM My wifi had an issue. So I reconnected and everything was fine, but when I tried to sign into Minecraft after turning it off and on after wifi was working fine, it would not let me sign into my Microsoft account. Tried uninstalling, reinstalling, turning off and on, deleting save data. Nothing works. Please resolve this as I want to play with my friends but with this issue I can't.
I tried clearing it over and over, only fix was to fully delete the minecraft save data from my nintendo switch.