Need Feedback on Rejected Image Due to Quality Issues

Hello everyone,

I’ve recently submitted several images to Adobe Stock, but unfortunately, many of them have been rejected with the reason stated as "quality issues." One of the rejected images is attached below for reference.

I'm trying to understand what exactly might be wrong — is it the lighting, composition, realism, sharpness, or perhaps some technical detail I'm missing? The image was created as a transparent PNG in a clean and isolated style, and I’m unsure why it didn’t meet the quality standards.

I would really appreciate any honest and constructive feedback from fellow contributors to help me improve.
Thank you in advance for your time and guidance!