Is there anyway to get my account un permabanned?

About a year ago I stopped playing league and gave my account to a friend because i wasnt playing anymore, within a couple months my account was permanently banned for toxicity. I realize account sharing is not allowed but I thought I was done with the game anyway so I didnt care much at the time. I want to play the game again now though and was wondering if there was any way to repeal the ban. I dont believe I had any prior bans or even chat restrictions before I stopped using my account and my friend started using it, there was also an extreme difference in rank as i had only made it to silver something whereas when my friend began to play, the account was diamond before being banned so based on rank and chat logs its fairly easy to tell it wasnt the same person.