Azir's Ultimate. Bug.

Azir's ultimate has been failing it's main purpose, and that is to knockback champions after the skill has been activated. This bug in particular happens mostly when Azir does the combo, " W, Q, E and R". Enemy champions don't get knocked and this has been a very big problem with Azir because it pretty much destroys the purpose of his ultimate. This bug has happened many times in Normals. I even tried to test it on a " Costum game" with bots and the bug keeps happening. If riot would take notice of this bug, it would be of great appreciation that it can be dealt with as soon as possible.