Animation Issue?

Hi, really simple here
When I run my animation in jMonkey, after the last frame, it will play 1 frame in the rest post, then restart the loop.
This is quite annoying. What causes this to occur? I am fairly certain that I know how to fix it, just interested in why it does this.

Actually, I can’t figure out how to fix it. It’s like 1 frame after the animation ends, isn’t played right, then it restarts.

try to remove the last frame.