This kind of red rash can be due to contact dermatitis, stasis dermatitis, hypertrophic lichen planus or fungal infection( usually it is itchy). I suggest you to get an evaluation done from a dermatologist. Till then keep your leg elevated while sitting and apply some calamine lotion of the rash.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.
thank you for the response. I really dont know where they came from. now its nothing and they became dark spots.i leave to work for 10 days due to ramadan. if im going outside, working or doing something its appearing. I will post some picture what they look like.