Perma banned after month break (hacked)

Came back to the game wanting to try out PBE and play some aram on main account (am active on a separate account), and couldn't log in. Saw that my name was different on the forum, curious i checked from my other account to find my main accounts name is different, and to my shock has been active for the last week playing various roles, champs, builds, and modes. most of the games are actually duo'd with up to the same 4 people.

After logging into the account I find I am perma-banned for use of third party software. I have used nothing for the game, inside or out. I supposed whoever hacked it did...but they didn't even change the log-in info. I have never given my account info to anyone, and no one else has access to my computer, and I don't even use the email associated to the game. I believe my email was changed however, considering i'm not getting emails from attempting to log into the PBE client. I have submitted a ticket, was just wondering if someone else has had this problem, or if a riot employee sees it by chance.