I completely understand your concern and I hope I am able to help you for the same.
Now you seem to be having macular amyloidosis
This is a pigmented skin condition.
There occurs skin deposits of amyloid protein.
But is is essentially harmless but cosmetically, looks bad.
Do not rub the area, as it will increase the pigmentation.
You need to apply a lightening agent like kojic acid
You may see a dermatologist
for other measures like chemical peeling.
Hope it helps,
Dr Geetika Paul.