i was log in my account and then a message pop up saying that my account was login a different place and i got kick out, then i try to log back in and it saying that my password or username was wrong, and i know that my username was not wrong so i keep trying my password but it didn't work, so i log on into one of my smurf account that i use to play with friend and i added my main account and im seeing that my main account was online and i try to talk to who every using my account but he log off, then i try to log back into my main account but it didn't work then i go on the league website, luckily i keep my main account log on into this computer, then i try to go and change my password but the old password didn't work, then i try to change my email address but it didn't work either so i when and look for help online and found post that stated that if this happen, that mean your account was hack.

My summoner name was cookiezlion

Submit a ticket on support, u aren't going to get any assistance form Riot here.

Best of luck