Unity Asset store declined my asset for "too simple"

(First time posting a question)
I got mail from asset store team today that my asset declined because its too simple.

But i dont think its too simple. Screenshot attached below. Its a 2d character with animation spritesheet for platformer games.

each character comes with 4 Animations.

What to do next? Is this asset is not ok?any problems
with this asset?

After googling this issue, it seems to other people have this issue as well. It might not be your art, it can also be the way your asset is presented. As they say it is too simple, it might be the case that there are already similar assets on the store or that the asset doesn’t meet the “Asset Store Quality Standard” whatever that means.

"If you did not receive much information, there may be too much which needs to change for the asset to meet the necessary criteria to be accepted.

The Review Team usually provides specific feedback via email. Generally, if the Asset Review team has suggestions to get the asset to the standard it needs to be, they will provide you with some tips in their reply.

When developing your asset, you may be able to increase your chances by keeping in mind the following points:

We want to encourage diversity in our store as much as possible, so if there are already similar assets on the store to the one you are developing, it will be less likely accepted.
The art style needs work. If the asset does not currently meet our standards, it will not be accepted. We want to host the best possible assets for our users.
Your asset needs to meet the submission guidelines. Please review these to be sure that you have included all necessary files."
Source: https://support.unity.com/hc/en-us/articles/205754275-Why-was-my-asset-declined-

I think if there was something wrong with the project setup they would have told you, but it might be wise to check chapter 2 of the submission guidelines: Unity Asset Store Submission Guidelines - Asset Store