I need some feedback as to why these haven't been accepted
Adobe always give a reason. What did they say?
All of the photos are showing the same proble. Overexposed highlights and underexposed shadows. They need more middle tones and they are too soft.
How do can I fix that problem?
You can possibly fix the underexposed and overexposed areas using Light Room or Photoshop, as long as those areas aren't clipped. Whether or not you have clipped the highlights or shadows is displayed in the Histogram. You can also use Dehaze, contrast and sharpening to give the image a more crisp and detailed appearance. However, if the main problem is lack of sharp focus, you can't fix that.