It was rejected because of focus and exposure - it isn't very sharp and the picture is not correctly exposed. The composition needs some work as well.
Also, there are gazillions of flower photos in the stock library, so don't bother with uploading flower pictures!
Underexposed and unfocused as indicated by @ricky336. It would be a better composition if you excluded the distant background at the top and filled the frame with the purple flowers, properly focused and exposed of course. Nevertheless, you should be aware that Adobe Stock is absolutely saturated with floral images - more than 27.5 million - so yours would have to be technically perfect and unique in order to be accepted or ever sold.
Alright...thanks a ton!!