sole of my right foot

i’ve been to all the specialists and the problem persists in spite of many kinds of treatment.
what I need is A DIAGNOSIS.
the skin of only ONE foot has been thickened, peeling, itching, red (it looks like my foot has been burned) and the red/peeling areas travel up the sides.
looks like i’m wearing a red sock!
it’s not fungus.
it’s not contact dermatitis.
i’ve had it for YEARS, but it’s worse now than ever.
clues, please!!
thanks