It is a nice picture, but it displays color noise and is lacking contrast. The hair blends in with the background. There should be clear distinction between both in case a customer wants to change the background.
Please find attached some non-technical notes I have made.
Apologies in advance for handwriting on your work, I found it quicker and was with the sole purpose of providing some help beyond the "plain" rejection legend we all might have get once or more in our work. Photos are assumed to be yours. NO plagiarism intentions of any kind at all are pretended from my part. I hope this contribution helps to cover one part of that "big void" of multiple possible rejection reasons.
I am not an Adobe employee nor anybody to convince you about anything, I am just a volunteering dude trying to help people blowing off some steam when their work is rejected.
In other words, trying to provide an "out of the box" perspective. My contribution is with good intentions only and hopefully will produce at least one smile.
For more formal and professional comments listen to the guys that clearly know what they are talking about.
Keep shooting, learning, observing, and specially, having fun!
PS. Lovely work
I think the composition could be improved a bit. With the head facing down, it is a bit of a blob - the head. The person could lift up their head a bit and show some of the face. Also, the hair is distracting, and not focused very well. You could also reduce the highlights a bit.