I got banned

So tonight i randomly got banned for MMR Boosting, apparanlty someone has been logging into my account and play without me knowing. I am not sure if its because at the beginning of the season i have been back and forth plus i hit gold 5 then stopped playing ranked because ranked is too much pressure for me to handle. Riot please help because i am very confused, i finally got a break from school and i just wann aplay some league of legends