rejected for technical reasons

Your depth of field is too shallow and focus fell in the wrong part of the composition, leaving the bee mostly out of focus. 

Focus and exposure.

Look at your picture at 100%, and you will see, that the focus is somewhere in front of the bee, instead on the bee. 

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
and especially quality and technical issues: https://helpx.adobe.com/stock/contributor/help/quality-and-technical-issues.html