From the symptoms it can be dry skin or xerosis, contact dermatitis or sweat dermatitis. As far as the treatment goes, you can apply an anti-itch cream or lotion to the affected area. Oral antihistamine, such as Benadryl can be taken. You should take a comfortably cool bath and wear smooth-textured cotton clothing and also choose mild soaps without dyes or perfumes and use a mild, unscented laundry detergent when washing clothes, towels and bedding. Application of calamine lotion helps in soothing the skin.
If the symptoms persist then please consult a dermatologist. I hope it helps. Take care and please do keep me posted on how you are doing. Kind regards.