Riot please help with the trolls

hello all i am a recently reformed player.......... im trying very very hard to not be the toxic jerk i was before and work with people but i keep running into trolls in my games and it seems they have no fear that what they do will have any consequences. * removed summoner name*... we started out normal in lobby, i decided as 3rd pick to go kindred mid which i have been doing a bit recently and for me is pretty good and working well. since i did this he decides that "i just got promoted and im at 0 lp so im gonna troll and go yasuo and ruin your game"... he even said so......so game starts......... he goes to bot lane with our adc cait and steals most of her cs forcing our top lane trynd to take jungle and our support morgana to take top lane....... everything seems to be going ok just a little cs missing from adc...... then he comes mid and completely destroys my cs and follows me around the map taking whatever cs im trying to farm aka jungle camps/other lanes..... we are doing ok even close to winning then we have one bad teamfight and he lets the other team just push mid and sits top lane and lets them take all up to our nexus for their win. we end game i report him and let him know that he cant be acting like this its not right........ he proceeds to say that it doesnt matter people that spend rp on accounts only get warnings and will never get banned and he doesnt care......... im really upset by this....... im a nice player i dont do troll things like that........ i had some bad games where i get upset and say stuff and i get a 2 week ban yet trolls like this that actually ruin the game still run around free and trolling..........it makes it hard to reform and not rage at someone that wastes 30 or more minutes of your life and ruins your fun Riot.