Varus Q Bug

When i press Varus' Q, it does nothing. I kept spamming it over and over and it still does not work. It happened when I played a ranked game and i almost killed an AD carry. I was going to press Q so i could kill the AD carry with that but to no avail, it did not work. Varus is one of my favorite AD carries and hes fun but with the bug he's having, nobody plays him anymore. Please help with this bug riot.