Apologies for the delayed response.
This ban was not based solely on the "joke" you made. You also have a history of toxic behavior and edging rule 1. This is not an isolated incident. And jokingly breaking the rules is still just breaking the rules. Appeal denied. You may reappeal at a later date.
It would do you well to also understand that we do not ban people for no reason, and to be more patient. The responses in this thread don't help your case.