Account go banned but i dont play for a long time... why?

Hello communnity i need help i dont play LoL for a lobg time, wanted to star again today but as i signed in with my account i fpund out i have banned for severe actions. I dont play for a year maybe qnd the datr of the email i received is from august, like i said i dont play for a year or so. Maybe mu acvount has been hacked or someone found out my password and did something with it? I really want it back i sent a ticket but no response. How can i get help to solve this? Thank you very much