tahm kench ult not able to reactivate (go to destination)

while playing on team builder second game with tahm i tried using my ult and it canceled on me went on a 10 second cooldown i thought maybe i took aggro from something so i tried again same thing happened even tried having people jump inside me with my ult it would cancel and id have to use w to spit them out or wait for it to end. i tried it about 15 times since it always went on a 10 sec cooldown im not sure what caused it i bought the same item i did the previous game and was playing support so im not sure what the cause is but the other tahms ult was working fine or so he said