Sion's very stopable unslaught. (Q AND R stop working half way through game as supp sion)

Twice now, while playing support Sion in bot lane, I have had a glitch were halfway through the match, my Q and R stopped working. It did not matter if I clicked on the icon or used the button, it refused to go off. the strange part is that it worked fine in the beginning of both matches but some where around the 40 min mark it just stooped.(Also, I had played a game as support Sion and finished the game just fine. But when a went to play again that's when I got the glitch.)