Twitch Ult is Glitched on ARAM

Hello I just got done playing a ARAM and I notice that when i was using my ult on Twitch everytime I would use it on someone and some one hits me while I was using it it would reset the CoolDown on the ult instantly. I just found it to be true on ARAM but I notice when we all was done with the game. I believe this is a glitch because that is a long CD and I don't think that would happen normally. Thanks for your time.

Shackmanpro