Thanks for posting your query.
You are most likely suffering from "Candidiasis" caused by normal commensal fungus candida albicans.
Human body has few protective mechanisms which prevent proliferation of candida albicans.
Frequent washing with soap and water , excessive antibiotics use removes this protective mechanisms and proliferate this fungus.
You should again consult with dermatologist/ internal medicine specialist and should go for proper check up.
You should apply antifungal ointment in spite of Mycoderm powder or oral Itraconazole
Application will stop proliferation of fungus with faster recovery.
Dr. Mayank Bhargava