Master Yi Q CD bug 6.21

So I was playing a Ranked game and then while in a fight my q was off CD and I pressed q but it said it was on CD, so I looked to see if it was on CD and it was fine so I just dismissed it. Later in the same game the same thing happened and I was getting frustrated. I used the "alt + q" to see if it was on CD and it said it had 5's CD left. I wanted to point this out. i just posted this after my second game with this bug and i dont know what is the cause of this.

Summary - Master Yi's q is bugged were it shows its off CD while its not.