How to appeal for a false enforcement action?

You'll have to go to
enforcement.xbox.com

As mentioned your only option is to wait a year until you're allowed to apply for the Ambassador program. Your time to dispute the Enforcement Action has passed and its unlikely it will be overturned at this stage. It's also hard to prove you were hacked
unless you filled out the account recovery form. Support wouldn't give access back any other way due to privacy laws.

You would havr to wait a full year after the enforcement before you can apply

Fyi if you were hacked you have to contact support

And open an unauthorized access case and let support deal with it they will investigate and work with the PET

While.this occurs your account is locked

So unless you can get that enforcement action removed from your account (most likely you will need to contact customer support) or you can explain the situation to an Xbox Ambassador Community Manager ( I think that's what they're called these days) and
they grant you an exception you won't be able to join

So unless you can get that enforcement action removed from your account (most likely you will need to contact customer support) or you can explain the situation to an Xbox Ambassador Community Manager ( I think that's what they're called these days)
and they grant you an exception you won't be able to join

Customer support has nothing to do with enforcement and actually have 0 access to removing enforcement actions. They would just refer him to the enforcement team page.