This photo was rejected, what was the reason for this?

This low-res preview is too small & too blurry to critique.

Hello,

The cropping is a bit tight.

Adobe Stock moderators review images at 100% magnification.
If the image is too small, they cannot verify the reason for rejection.

Based on this image alone, the only issue that can be identified is the need for lens peripheral illumination correction.

You need to post the full-sized version. We can’t tell much from the thumbnail. Bear in mind there is a 5MB upload limit, so you may have need to reduce the image to some degree prior to posting.