Can someone help?

My sons armpits look like this ( he’s turning 2 in August) he’s had them like this since he was born basically.. and I don’t know why or what to do. We’ve already been told by the doctor that it was a fungal thing so we put ointment but it does absolutely nothing. The doctor told us this when he was like 8 months old. Did your child have this and if so what did you use? Please help I’m concerned.