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It seems to be a fungal infection
even though it is not itchy.As you said it goes off with some creams and relapses again ,means that you are using probably a steroid
creams which vanishes it temporarily .
I would advice you to use a plain anti fungal cream (no steroid) for couple of weeks and see the response .If it doesn't go ,then you should consult a dermatologist
for expert opinion.