"Aren't able to create lobby, pls exit client and try again..."

This has been going on for days. Almost every time I log on it says that. I close client and re-log. Sometimes it works, most of the times it doesn't. I've tried Hextech tool, clearing cache, everything. After playing an ARAM game, if I click anything but play again, the button blacks out and it happens again. I've seen others saying similar things but nothing has been discussed or offered as help. ANYONE?