How to make an loop animation?

I'm using 2018 version, I checked the loop time and switch the warp mode to looping, however when I put it in the game it does not looping at all, just play once and done with it. I search for solution for whole day and all I find are whether outdated answer or people who trying to stop their animation from looping.

 

If it "plays once and done", more likely its something with your State machine or code you use to run it than with animation itself

 

@david873025517 I assume you are trying to use Mecanim, so see the manual for the basics:
https://docs.unity3d.com/Manual/AnimationOverview.html

You should make a state for your animation, one of those blocks you see in the manual images. Then make a transition to it, and also from it to your default state (for example) and then set a rule when to enter and exit (see the Conditions area in Inspector when you select that transition line.) You could use a boolean which you add to the Parameter area in your Animator window.

 

Thanks for replying, I guess it was because the script.