[Gameplay] Vi's q stops working

It has happened twice now where ill be playing as Vi and my Q vault breaker stops working completely. I wont be able to activate the skill to charge it up or anything for the rest of the game and essentially am left with 3 skills instead of 4.

Each time its happened to me its been when

1. I activate q to charge up
2. I die from some source of dmg immediately after

Not sure if it breaks if I die right as i hit q to charge or shortly after