Maestro Error wtf ??

I started lol i went to play a rank, i picked my champ and all of the sudden my league just crashed, i tried to oppened again and dint let me, so i restarted my comp i went on to my league folder start it again, and when i got in the game we lost. riot idk what error that is but please fix it, because of that error i losted 20 lp thanks and have a great day.