Mouse Right-Click not registering half the time

Hey y'all, Basically, what happens is, when I open League, my right clicks start f'ing up. They wont register half the time or keep clicking, be it in game or on my desktop. For example, if I fast click on my Desktop, sometimes it'll register as if I'm dragging my mouse, doing the multiple selection square (Blue square to select multiple things). In game, I can click around once every second, which isn't too bad, but it easily becomes unplayable when it comes to dodging skillshots or in teamfights. The thing is, I've already verified it's not my mouse, as it litterally starts happening only when I open League. It goes away after either 1 game or like 45 minutes being alt-tabbed, which is far from ideal. I've already tried the file deleting thingy (persisted settings and the other 2 I can't remember the name) and I'm out of ideas and it seriously ruins the gameplay for me. Any ideas/suggestions?

Tl:dr: When I open League, right clicks work half the time, tried file deleting doesn't work, problem doesn't come from the mouse.