I cannot confirm anything without examination but it can be due to sweat dermatitis,eczema or fungal infections.
Most cases respond to over-the-counter products
, which contain any of several basic ingredients: miconazole, tolnaftate, terbinafine,ketaconazole and clotrimazole.You can consult a pharmacist and get any cream or lotion containing these ingredients. Some of them are Lamisil, Monistat derm, Mycelex, and Nizoral.
If the symptoms persist then pls consult a dermatologist.