Your picture is too blue and too saturated and the pixels are too smudged - which has come from the noise reduction being used in camera - typical of smartphones. If you enlarge this the quality begins to fail. For stock, the images need to be clean and able to be enlarged without any faults showing. For this reason, generally speaking, smartphone pictures tend not to do so well on Adobe Stock.
Have a read of this. It's a brief guide on image quality:
Thank you so much for the feedback. This was very helpful.