Hello and hope you are doing well.
The probable causes for itchy soles are scabies, diabetes mellitus, eczema, tinea pedis (fungal infection) and psoriasis. Scabies infection is caused by a mite Sarcoptes scabiei, it burrows in the skin folds of hands and feet and causes intense itching mostly at night. You may need to consult a Dermatologist who will examine you and may ask for blood tests and in addition examine the scrapings from the skin to arrive at a diagnosis for appropriate therapy.
Hope this helped and do keep us posted.
Hope you find an answer at your doctor and feel better soon.
C~