I have been blocked on SU discord for being underage (which I'm actually not) i even asked on the SU wiki about why this happened, but i got blocked after receiving a reply by a bureaucrat. A few days later, i went to Piierogii's wall and told her that i am not underage. Heres a link to the wall: https://community.fandom.com/wiki/Thread:1819509
Blocking is at the discretion of local admins. You've made clear they made a mistake due to a mix-up of terms, you can't really do anything else about it. It's best not to pester other admins with it, as that can be considered harrassment.