If you have any problems with your account, such as being hacked, basically throw yourself off a bridge. You will be banned from all the servers you are on, and no way to reach out to any admin of those servers. The discord support while helpful cannot really do anything to help you either. So if you do not know anyone in the groups you just got invited to, you are out of luck. Nothing you can do, even setting up a new account is pointless since they ban your IP and looks like any other account or IP address associated with that account. Jumping off a bridge is more fun than trying to fix this.