Ability being disabled

I don't know if this occurs with other champions, but I have been finding that with Vi and Xerath that when I die right as I activiate the ability on my q after the charge up, it gets disabled for the rest of the game. The key moment is when i die right as I click q to use charged arcanopulse/vault breaker. This i the 4th time that this has happened to me and really cripples the ability to play. Afterward the icon appears normal but won't do anything other than make a clicking sound. No idea if it's just me or prevalent in other people's games.