Help! Can't see my cursor ingame on full-screen

Hey everyone. I really need help: Whenever my game starts, the cursor is gone. (the golden hand ingame) but when I click, my character does walk. I NEVER had this before until this patch. I use double monitors. When I move the cursor to the far right (so towards my right monitor, away from my primary one where League is on), I can see the golden hand slightly appear on my right monitor. so it IS there, but doesn't go further from the edge of it. But in-game, I can't see it at all.

I can only make it appear back when I am windowed or borderless. But I cant play like this because I have FPS lag then, no fun to play.

I already restarted league entirely, doesn't work. Restarted my PC, doesn't work either. I tried Alt + tab. Alt + enter...really nothing of this works at all. Please help, I can't play at all now. :(