ruining placements purposely and bringing team down

It was my first placement game for ranked. My support the Lulu and I the adc, Jhin, went to lane. Lulu was poking Thresh and Jinx too much in my opinion, but i poked with her constantly. It got to a point around 4 minutes where they went too far, died, then blamed me without a reason. I asked why but they kept giving me negative speech. Even my teammates agreed Lulu was wrong. Then Lulu stood under our bot turret and didn't help me push lane or farm, which resulted in me dying, and them blaming me. That's not entirely my fault right? So then Lulu decides to head mid and take mid's farm which made everyone even more tilted. We lost, everyone reported Lulu and we left. I hope this gets noticed so that someone can fix this players mood because you never know if that person got banned or not when they should've (no I don't think it's a harsh idea, because it was in a placements match!). I wrote this thread because I very much dislike players like this, ruins the game for newcomers to competitive play like myself. Thanks for reading!