Technical Issues

There are many artefacts and highly visible luminance and colour noise in the picture. I would also guess that the white balance is slightly off.

Not to mention a slopping horizon.

There are quite a few issues.

Another article you can also read:

https://helpx.adobe.com/stock/how-to/tips-stock-image-acceptance.html?set=stock--fundamentals--adobe-stock-contributor

Hi @OrionEdward,

Examine your images at 100-200% magnification and you'll begin to see all the imperfections.

In this case, it's too dark, too many artifacts, and issues with color balance.  

Adobe Stock looks for highest visual and technical quality. See links below.
https://helpx.adobe.com/stock/contributor/help/reasons-for-content-rejection.html
https://helpx.adobe.com/stock/contributor/help/quality-and-technical-issues.html

Also keep in mind that Adobe Stock have 8+ million excellent sunsets and sunrises in their database.  So you have much fierce competition in this category. 

https://stock.adobe.com/in/search?k=sunset%20on%20sea

Better luck with your next submission.