Varus' Piercing Arrow (Q) [GAMEPLAY]

A number of times while playing Varus late in the game, his Q ability no longer works for the remainder of the game. Neither reloading the game nor restarting LoL has fixed the problem for me. From my experience it seems to happen most when i cast it almost simultaneously as i die. This bug has been happening to me ever since i started playing varus at the beginning of season 4 and still is going on. Varus is my favorite champ, please fix him:)