itchy skin

hello i have a skin problem for 3 years now, it itches (itch) a lot i used some ointments indicated by doctors and it didn’t solve it, i did the scraping to find fungi also didn’t appear fungi, what can it be?

What was the ointment recommended by your doctor?

betamethasone dipropionate + gentamicin sulfate

this itch is only in one region, it does not spread, I wear socks, it does not spread to other regions.