Photo rejected for quality issues

Some friendly advice since you're new to Stock.  Read your Stock Contributor User Guide carefully.  It contains much important information.

• https://helpx.adobe.com/stock/contributor/help/reasons-for-content-rejection.html
• https://helpx.adobe.com/stock/contributor/help/quality-and-technical-issues.html
• https://helpx.adobe.com/stock/contributor/user-guide.html/stock/contributor/help/photography-illustrations.ug.html
• https://helpx.adobe.com/stock/how-to/tips-stock-image-acceptance.html

Adobe Stock customers expect the highest visual and technical quality for use in commercial projects.  Take 8 of your best quality images, examine each one at 100-300% magnification in Photoshop / Lightroom.  Fix the technical issues if you can, discard the ones you can't.   With what's remaining, compare your work with current Stock Inventory.  Is yours as good or better than what's been contributed?  If yes, submit it.  If not, don't.   This will cut down on your rejection rate.

The next hurdle is selling your assets.  That begins with a sizable portfolio of diverse subjects that customers are likely to search for...

Good luck!

You have to focus exactly on the heart of the flower. That is not the case here. (screenshot at 100%)

The picture is also a bit on the dark side. Some background should be visible.