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It could be a sign of a skin infection
. Is it very itchy as well. You need to keep the area clean and dry at all times. Maintain good hygiene. You can try applying antibiotic ointment under medical supervision as a trial or better to consult a Dermatologist
who will rule out bacterial/fungal infection
possibility. Eat plenty of fresh fruits and green lafy vegeteables. Drink plenty of water. Avoid sun exposure.