Rejected because of technical issues

General considerations: Shoot raw not JPEG. When you post here, post the image posted to Adobe stock, not your JPEG, with the editing applied non-destructively. This gives us false impressions if we do not check the assets with the same software you used. Our comments apply probably all on the unedited JPEGs.

Last picture (edited with Lr/ACR):

If you look at the histogram, you see, that your image is missing blacks and highlights and whites.

This gives your images a flattened look with missing contrasts.

You have quite a few sensor spots, and a lot of noise. You try to correct the colour noise, but ignore the luminance noise:

In addition there is an IP violation. You need to photoshop out all logos and markers:

For your second: I'll simply refer to @Jill_C's and @RALPH_L's assessment. Just one additional remark: If you are sensor spots, you will see them always in the sky. Easy to fix if they are only a couple. You need, however, to decide on a sensor cleaning.

The settings for your first image are interesting (edited with Lr/ACR): ISO800 and 1/4000s on a static object. Don't push ISO, if you do not need. There is no excuse to get such an image wrong, as you have all your time to check the settings, taking numerous pictures and selecting the best one.

It's largely out of focus and noisy. Your editing is too much and too less. You push the shadows to a 100%, the highlights to -100%. If you need to do those extremes, you made an exposure error. You would have needed to choose a different POV and framed the stones according to the golden ratio. But that are minor corrections to be applied. The major problem is the noise level, that you won't be able to correct. You also have chromatic aberration: