UI gone when reconnecting

Every single time the game has given me the red disconnect I get booted - not once have I stayed in a game.
I’m able to immediately join back however, to a broke UI that doesn’t let me do anything other than run around and get penalized.

You mean the hud or players being wacraft3 wisp? If is the hud, try Alt+Z on pc. If solves, close the game normally and reopen it. Due on crashes the game doesn’t preserve changes and often revert previous values. That or when you get disconnected you accidentally pressed Alt+Z, so if is the case you can rebind those keys.

If the wisps, you can still play but wouldn’t know much what it’s happening.