Photo rejected due to technical issues

In addition to the focus, it has a noisy background and could be cropped better. Read about the Rule of Thirds.

Hello,

Focus for me is a problem. It's just too soft, as well as white balance - it's too cool looking, and composition is not that good either.

Have a read of this from Adobe about how to create better photos:
https://helpx.adobe.com/stock/how-to/tips-stock-image-acceptance.html?set=stock--fundamentals--adobe-stock-contributor

There are 100s/1000s/1000,000s of flower photos on stock, so yours I'm afraid, just isn't up to what can be found.