Shame on you

Only God knows why MTN allows third parties like Mondo to have access to their customers. Some ****mer from Mondo called me and offered an upgrade on my contract and I will forever regret taking that call. I was offered 80gb for R199 on the phone inly to realise that it is actually 40gb for R199. I have been trying to cancel it since it happened on Monday but I am being sent from pillar to post by MTN agents. Why do you allow ****mers to have access to your customers? Am I ever going to be assisted with this cancellation or we must wait for 10 days just so I can be charged for cancellation. I have been with MTN for many years and I have never so disappointed.