Hello. I've had this issue for about 2+ years now and I can't seem to figure out what's wrong with it. The skin located around my stomach region has become darker and also rougher. It's also constantly dry, despite putting lotion on it to moisten it up. On a normal day, looking down on it would reveal a grayish color, indicating the dryness of the skin. When I scratch it, it gets ashy and leaves a white mark. It's odd because the lighter looking skin around the darker region feels smooth and normal. There are also small little patches of lighter-toned skin within the darker region that feels normal. For example, the skin inside of my belly button feels smooth and normal.
At first, I thought that it could be caused by me using my shaving razor to shave off the hairs that grow on my stomach. This was because the darker and rougher patch of skin is only on the region where I shave my stomach hairs. This would make sense too, considering the inside of my belly button is smooth and I can't fit my razor in there. However, there is also a chance that it is not caused by my razor. I've tried to not shave the area for two months, but it didn't help with any of the problem. At one point during the early stages, I was able to scratch it all off. When in the shower, I would use my nails to scrape it off, and it would come off as little bits of dead skin, but even now when I try to scratch it off it doesn't go away.
When I suck my stomach in and slouch while sitting, the skin wrinkles up. Also, when you look at it close-up, you can see that it makes up a little pattern of rectangles, much like a close up of a plant cell. Please help. Any solutions or possible diagnosis can help. By the way, it doesn't hurt or anything. It's just one of my biggest insecurities whenever I take off my shirt, since I'm still fairly young. I'm in my 18.
Pictures of my stomach area:
https://imgur.com/a/q965G4U (general picture of darkened skin)
https://imgur.com/a/tYWGmXL (you can see the rectangular pattern in this one)
https://imgur.com/a/9IrW3Ot (ashy white mark from scratch & wrinkles from slouching)