Hello, as far as I can tell you are not on our ban list on the discord. If you are unable to join you may need to make a new account as when you were banned you were reported to the Discord Trust and Safety team for violating the Discord ToS. You also may need to contact Discord Support and inform them that you were reported at the time but you are now over the age of 13 which would allow you to have a discord account. There is a chance that you are shadow banned on their end and if so there is nothing we can do about it.
Disregard all of this if someone else unbanned you and informed you elsewhere but as of now there is nothing that I can do if that is not the case.