MTN Contract Upgrade

I received a call fromTreven Pillay, who said that he was phoning from MTN, and that I was due for an upgrade. I questioned this, as my contract was only up for renewal in November, but he was adamant that it was renewable now, and asked whether I was happy on the package that I was on, to which I rep**** that I was. He subsequently said that I could go onto a sim only package, with the exact same benefits, for R139 per month. I asked about when I wanted to get another handset, to which he wanted to know, which handset I was interested in, to which I rep****, an iPhone 8. He then responded by saying that this handset would only be available in February next year. I have subsequently been notified by the IStore, that it will be available, later this month. Anyway through persuasion, and going on his word, I decided to upgrade my contract to a sim only contract, which he had stated categorically, that it would be exactly the same as the one, that I was currently on. On receiving the summary contract later that day, I noticed that the upgrade had reduced my SMS bundle from 400 per month to 200, and data bundle from 500MB per month to 300MB. Only on phoning their customer number did I realize that this was not MTN that I was talking to, but a 3rd party company, who had my confidential information, that I had supp**** to MTN in good faith. I find this totally unacceptable, and demanded that they reverse this transaction immediately, to which I was told, that they would have to listen to their recording of the conversation, which could take 2-3 working days. I immediately contacted MTN, who couldn't assist, because they hadn't done the transaction, although, as stated earlier, I was led to believe, the said Treven Pillay was from MTN. This business practice is highly *********, and promises made, are not what actually happens. Also the fact that my personal information is been made available to a 3rd party company is totally unacceptable, and I expect a full explanation from MTN on this.