One time while I was playing in a 5v5 match with Sion. I was doing well and my team was winning. Suddenly, the Q and R commands were not working on Sion. Still won the match. I thought it was from the ability of one of the enemy champions even though I didn't see a status on Sion, I thought nothing of it. It then happened to me again yesterday; the team lost the match. I decided to look into it and found out that Sion has a bug! My favorite LoL champion has a bug! I have not used him since and switched to a new champion, Wukong. I do intend to play Sion again but I do not see Riot Games fixing his bug soon since apparently this has been happening for a while (more than a year). Hopefully there's a fix so I do not have to worry about it.