Based on the provided source material, there is no information regarding a city named Yona in Zambia. The term "Yona" refers to an ancient designation used in Pali and Prakrits, as well as its analogue "Yavana" in Sanskrit.
In Ancient India, these terms were used to identify Greek speakers. They are transliterations of the Greek word for "Ionians," who were likely the first Greeks to be known in India.