Lee Sin Not Being Stunned Properly

In some of my recent games, when I play TF, I play against a Lee Sin mid (cause reasons). However, when I stun his with my gold card mid q, he still has the ability to auto attack me when he is stunned if I am in range, which I always am after he q's to me. Annoying cause it can give him stormraiders or thunderlords which he wouldn't get otherwise, and often causes me to die. He still can't move during the stun, but he shouldn't be able to auto attack me either... right?