Sprite not changing flipbooks

I’m trying to get the sprite to change to a flipbook at the beginning of a function. It’s only meant to play once and then change back to its idle animation:

I set looping to false so that it ends, as I have a function BINDED to OnFinishedPlaying that sets looping to true and changes the animation back to idle. However, when this function fires off, the sprite doesn’t change. At all. It just stays as the idle animation. I don’t know why.