hello why i cant this image,it is rejected

Noise and artefacts. And I would say that having the focus on the plants in front is a bad decision. If this was a phone camera image, you should avoid that fake DOF, as that never works well. 

There are also spots in the sky. Birds or dust.

Hello,

The lens flare, even though it might add atmosphere, isn't good. It does not add to the composition, so this can be a reason for rejection—among other things.

Noise and very little in focus are the primary issues.