Vodacom ****

We have had a really bad, horrible experience with Vodacom, my father is a pensioner. He was contacted by Vodacom and they made false promises to him, by telling him that he was such a good customer because he had been with them for years and they are going to upgrade his contract free, no charges added, after he asked them multiple times that question. Is it going to cost more, the lady kept repeating no all cost are going to stay the same. Well, it was a lie! After contacting them multiple times they said they would change it back to the way it was, more lies! What can we do? Does anyone have any feedback or suggestions for us! This isn't fair! Vodacom are ******* and filled with *****! Please help us! They don't even deserve one star!