Originally Posted by hamhead

Even one incorrect entry of the PIN can do this. I've gotten locked out of many of these cards just either remembering the provided PIN wrong or fat fingering it.

Sadly it ends up being at least a $5 mistake - either you have to buy a new GC with that GC running it on credit or you can liquidate it via a CC method (Redbird probably the most viable option now), but that carries the opportunity cost of losing the ability to use a points earning card.