FindKnight

Errors do occur especially with translations not only in Minecraft. But this is a bug so this will be fixed 

This is due to Minecraft's filtering system. Minecraft doesn't support profanity and the first 3 letters of your name registers as trying to say a swear.

Minecraft is just very picky and trying to make a safe environment for the younger audience even if your not intending to swear.

Maybe your laptop doesn't have the standards to run Minecraft smoothly, I had that same issue but after getting a new laptop it resolved it. And I don't think this is a bug.

Same thing happened to my little brother. Are you under the age of 13 or 18 where you have some blocked/curfew settings? My father manages my little brother's account and that's why he can't connect to servers but can connect to offline/singleplayer.

Have you tried checking the keyboard controls in your settings? Maybe Tab isn't a hotkey for Xbox, was Tab working before on Xbox?