I have black patches in my chin area just below my mouth and on the sides of nose and at corner of my lips. Sometimes It will become very dry and peel of dried skin will come out but now it is just black skin. I am not sure that it is seborrheic melanosis, but around an year ago I consulted one dermatologist she told it is seborrheic melanosis but her medicines didn't work and she told it can't be treated permanently. Somehow it was reduced but again my skin has become very dark. How can It be treated permanently?