Hello dear
From the picture which you have attached here it seems to be kind of an allergic rash only. You need to start a proper course of medicines for it as it is completely curable and treatable.
Till the time you consult doctor apply oil coconut oil or moisturiser over that area
Next Steps
For any further query you can always contact me on my Facebook side that is Dr Atika Aesthetics
Health Tips
Avoid Cold drinks ice creams and chocolates