If he's that way inclined to ban you for no reason then you don't really want to be on his server.
Also, I'd just like to point out that he can't really be a 34k ID if his name is Blockhead36741.
Unless he specifically changed his name to that number.
Otherwise, by Default, the number after Blockhead is your ID. So he's actually a 36k ID.
Next time you might want to grab a picture of the actual ban message or some of the text from the game prior to the ban.
It's easier to trust someone's word when they provide picture evidence.
You can use PageUp to view previous text in-game.