Welcome to HCM,
Its difficult to precisely to say without examining.
Your symptoms could be due to many causes like eczema
, fungal infection
, allergic reactions etc...
You can consult a dermatologist
for detailed examination.
Till then you can try certain methods like keep the area clean and dry,
can use candid dusting powder to the local area, and anti histamines
available over the counter to prevent itching.