Maybe it’s your IP address? I’m not sure how Reddit does preliminary screening, they might be seeing your IP address trying to create a new account when you previous account was accessing from the same IP.
Also, what got you banned? Admit the silly thing you did.
I've had 2 accounts with over 100k karma each perma-banned for very similar reasons. If you access via the mobile app, they will also ban any other account you use the app to log in with.