Agent upgrading me without my consent / authorisation

I called Vodacom to get a quotation on an early cancelation on one of my contracts. The agent Nitesh told me he can make my bill lower by upgrading my primary nr. Or I could get a phone for R150. But he insisted that he could make me pay R119 sim only for 1gb of data and R150 airtime. I said that is what I am now getting he said but I am paying almost R130 or R140 for that and he can make me save. So I said I have my bill infront of me and it does not say I am paying R130 or R140. It says I am paying R114. I got irritated and said he must ma give me what I called in for and that was to get a quotation. He said the quotation was send and I said I can see it. Then we rang off. But minutes later I received smses that I have successfully upgraded and will start paying R119. I called again and was told I will be called and that the upgrade will be reversed. Instead I received now an email confirming the upgrade. This is utter nonsense called because my bill is more than R1200 and now Vodacom agents use ********* tactics to keep us in debt with them