About a month ago, I noticed a discoloration under my right arm pit that turned a lighter color than the rest of my skin color with a brownish pink frame around it. It is not itchy or anything but ugly when I have a tank top on. It is in the shape of the hair under the armpit. And I just noticed that where the color change is, the half , where the strange color is, does not grow hair any more. If anyone has an idea what this is that would be greatly appreciated. Thank you.