Dunk master glitch

I was playing ranked yesterday and got put in top lane so of course I went to pick my trusty dunk master Darius. In about the first 5 min I had a 1v1 which was ok I won the exchange, however after the fight I could no longer control my champion and he automatically began to fallow the enemy under turret despite my mad clicking away from them. As the game continued nothing improved ether Darius would fallow them or completely stop moving (I could control his abilities just not his movement). This has happened before but last time it was a normal n I just rest my computer after the game. This has only happened with Darius while using dunk master Darius. I was really frustrated and felt it was unfair to me and my team because it was a thrown ranked game. Please fix soon. -Mike Ortiz