Okay, this helps us narrow down the issue.
(Oh, and just so you know, “Play_Anim_Montage”, does not wait until the animation completes. So you need to add a “Delay” that is the length of your animation, otherwise the “Do_Once” will constantly instantly be reset)
Can you show the animation’s details? (By opening the animation and showing what the animation is supposed to look like. Along with the hierarchy).