These photos were rejected, I would like to know the reason.

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• https://helpx.adobe.com/stock/contributor/help/reasons-for-content-rejection.html
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• https://helpx.adobe.com/stock/contributor/user-guide.html/stock/contributor/help/photography-illustrations.ug.html
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Hope that helps. 

These appear to be mobile phone images; it would probably have been preferable to shoot in landscape rather than the typical cellphone portrait orientation. Composition is the major issue in both images, and the first one also has chroma noise.

The second image: Framing with the foreground is usually fine, but it's almost 50/50, so the foreground is too predominate. And cropping again.

The composition is poor.
The colors are off and a little dark.
Retouch the image in Lightroom or Photoshop before submitting it.

Have you prepared a model release?