sejuani "E" is broken

Seems really weird i go from game to game, chargin people with Q, then flailing (W), and then sit there straight up autoattacking people, and it doesn't gain stacks, and doesn't even appear? Is there a bu g or some reason why it just sits there and doesn't work AT ALL in a LOT of situations?

I just went up with a warwick, autoattacked him about 7-8 times and nothing happened, skill didn't light up, no 'frozen key' icon, nothing, just sits there completely broken doesnt do anythign,, what's the deal here?