Rejected because of quality issues? What might those be?

To add to what's been said about exposure & highlights, also examine your white balance to ensure it's not too blue.

https://photographylife.com/how-to-correct-white-balance-photoshop

Hi @Mikko24796132zol7 ,

Your file is underexpose with high highlights. This is what you need to do. 

Up the exposure to normal/average.

Reduce highlights (whites if necessary).

If you use Ps you can use the color grading to assist with some of these adjustments.

Best wishes

Jacquelin

The highlights are not the cause of the refusal.

Blacks are missing, making your asset technically overexposed.

I think that you also need to work on the exposure (middle part of the histogram) and the contrast/texture/clarity.

I think it was exposure. Especially highlights.