Chat Restricted......For PLAYING AP RENGAR? WTF??

For the past few games I've been testing out AP RENGAR because I saw a high elo players do that and own. I am positive in game and don't insult people. HOWEVER PEOPLE ARE REPORTING ME cuz im playing ap rengar. A few games ago, 4 guys were pre-made and they all reported me for playing ap rengar, despite the fact that we won and I did second most damage.

So why am I chat restricted for just playing the game? PLEASE LOOK INTO THIS.