Thanks for writing in.
The condition you are suffering can be contact dermatitis/haily hailey disease/seborrheic dermatitis etc
Treatment can be oral topical steroid
creams with antifungal creams.
Patch testing and skin biopsy
may be required .
They are available at dermatology clinics.
Also supportive oral tablets containing antihistaminics can be helpful.
Keep the area clean and dry.
cream twice daily.
Please consult a good dermatologist
for proper examination and prescription medications.
Hope this helps.