someone hacked my account and need an opinion

so someone hacked my account and luckely he wasn't able to change my password, and he was using my account for some time, and i only realised it because he changed my icon, i already changed my pass, never the less, he was playing with some guy by the summoner name of **redacted** and i wanted to know if it was possible to report him without having to play him, because he could be using a stolen account also, help me out
Report as:
Offensive Spam Harassment Incorrect Board