Fairfight isn't an exact science and a lot of people can unfortunately taste sweet justice the mighty ban hammer gives - Just a little while ago people were getting banned in the Grind mind because it's built around getting points fast.
Since opening regular tickets doesn't seem to be working (most bots and a fair amount of new agents only see the red flag and end the conversation), I recommend you call an agent instead of thriugh mail/text chat.
I think they should legally have to give you a reason why you were banned (just my assumption, not fact) so keep asking to speak to someone who can give you an answer. Of course, only do this if *you honestly didn't do anything wrong*.