Welcome to HCM
We understand your concerns
From the avilable description, the problem seemsm to be from allergic infection. Inflammation due to allrgens can heppen due to veriety of factors such as unhygeinic being, improper use of underwears, strong detergents or any foreign allergens etc.
In any case, the situation can become worse if you ignore it. Therefore it would be advisable to consult a dermatologist
for further advice.
Get well soon.