You didn't post the reason they gave you, so I'm going to guess it was technical reasons.
The photo is not sharp, it is noisy, it has poor lighting (looks like you used the flash in your phone), and the composition isn't very good (bowls cut off, dark blob bottom left, cup (?) at top, etc).
You are going to find it very difficult to shoot stock photography with a mobile phone. The sensor is too small, and the lens isn't the best. If you are serious about shooting photos for stock, invest in a DSLR or mirrorless camera and a couple of decent lenses.
Thank you, madscica.
I'm very greatful to you!
Also, if you view your photo at 200%, you will see that it is a bit noisy and that the
boarders borders have artifacts.
[Edited by moderator for clarity.]
If you are new to stock, you should consider these resources: https://helpx.adobe.com/stock/contributor/tutorials.html
Please read the contributor user manual for more information on Adobe stock contributions: https://helpx.adobe.com/stock/contributor/user-guide.html
See here for rejection reasons: https://helpx.adobe.com/stock/contributor/help/reasons-for-content-rejection.html
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