I just played with an intentionally feeding Nunu

Nunu followed rengar the entire game and stole his camps and told the other team to report us for baiting him to go jungle in champ select

Why is this the user still not banned after 3 similar games? Why does Riot not compensate the victims and why do I get punished for dodging if I don't want to deal with this kind of behavior.

I know many people will say "just dodge" but I was in placements, and a dodge is the same as a loss so I was willing to try to win at least.

This will literally set me back 5 to 10 games in order to attain my deserved rank. As a casual player that only plays 2-3 games a week this is really discouraging and translates to taking 5 weeks longer. I'm at a loss at what to do.