Is it from the Sunnah to keep repeating the cupping every month or every year if the person is ill or not ill?

For a normal person it is good to do cupping every three months. As for the sick person then every month because cupping is considered from the Prophetic medicine and he (salAllaahu peace be upon him) advised people to perform it. So it is a cure as well as implementing the Sunnah of the Messenger – peace be upon him.