Cant login? multiple clients and unexpected error.

Hello there riot games support. When i start op league of legends and try to login it either says "Authenticating..." for very long or it says a unexpected error occured while logging in please go to riot games support. So what i did is go into task manager only to see how there is 1 client open with a (3) behind it so 3 clients in 1 package and then another loose client lower in the list. these most likely have to do with my game not working and would like a fix as soon as possible. Thank You. I'm exhausted by searching how to fix this bug...