I have had a strange rash on the back of my head for a long time - probably a couple years. I don't usually cut my hair short enough to notice but the times I have in that past couple years I uncover this rash. It has stayed in the same spot and I believe about same size, may be getting larger. Links to pictures -->
https://imgur.com/a/EE9LHb7
https://imgur.com/a/3nYj6zy
Any help is appreciated. Thank you.