[GAMEPLAY] TAUNT (ability) BUG of Rammus, Galio whoever else

When the ability is being used on any champ. There is a chance that champion wouldn't be cc'ed successfully. As it's shown in the video. I don't know how to reproduce this. It happens from time to time used on any champion (probably on any, 100% happened to Akali, Lee sin, Leona). It happens I'd say in 1 out of 10 games. Video which is attached to this post isn't mine. Though I experienced this bug in season 6 in some games as Rammus. In s5 there were some. And even in season 4 it was all the same bug. Still isn't fixed. You can find more videos of this bug on youtube. Search: "rammus taunt bug".