Client turning black when it is time to ban champions.

Dear Players of the League and Riot,

today i had a bug where I played some blood moon games (I don´t think this has something to do with the bug but I just wanted to show, that it worked fine at this point). After the games is started a flex ranked game and when it was time to ban a champion the client turned black and since Ialso couldn´t select a champion after thegame was doged and I had to restart the client. After this i checked my ping, it was at about 34ms which is fine. So I thought It might have been a one time bug and tryed again. But guess what, the exactly same happened again. Over all I dropped from 73 LP to 60LP which is not that much but it is still a problem. I eaven reinstalled the client after this but now I cant log in (Riot is working on it). It might have something to do with the Ranked Problems they are fixing right now but it also might not so I thought it was worth the time to discuss the problem.

Maybe someone has an explenation for this, or a riot member could tell me if they are already working on it. :) It also would be nice if it was somehow possible to return the lost LP although I know this might not be worth the affort for riot. :)

Regards, Jack11126