Ammo Pick Up - cast failing

Hey! Haven’t posted here in a while.

I’m having a slight issue where I have a handgun that the player picks up and an ammo pick up that the player can pick up. The weapon functionality is absolutely fine, but within the ammo pick up, I am casting to the Handgun when the player overlaps with the ammo pick up, and calling a function within the pistol. Does any one have any idea why the cast is failing? Images are below.