League wouldnt let me login/after uninstalling and reinstalling the client broke.

I Q'd for a ranked game of TFT, and then the game crashed when we went into the loading screen, so I closed and restarted league several times, restarted by opening as administrator, but it would just tell me that there was a login error so I couldn't rejoin the game and now I just lose LP. I eventually tried uninstalling and reinstalling, and after I did that now when I open league I just get a broken client with a black screen. I tried looking up what do to about this but YT is lowkey useless and I can't really tell if this issue is my fault or not.