Cancelation of upgrades

I have been a customer of Vodacom for almost 30 years and have recently did some changes on my packages however I did not agree to 3 of my packages getting increased rates. I have tried to email and phone Vodacom continuously for the last week and no one is able to help me cancel those upgrades for me. I have been sent from one department to another and no one is taking responsibility of assisting me with my query. I am not cancelling my contracts, all I want to do is cancel the upgrades which I did not agree upon when it was sold to me over the phone.