Pathetic service from MOBILE PLUS and MTN

I am highly distgusted in MobilePlus and MTN. On Friday, 12 January, I got a phone call from MobilePlus telling me that they were giving me FREE 15GB per month as I have been experiencing problems with my data. Of course, I asked the guy on multiple occasions if I would pay additional fees and he continued to reassure me that I will be getting extra data for free at no additional costs! What makes me more upset is that this guy had access to all my personal information including my ID number. The guy then continued to mumble some T's and C's and once again said I would pay no extra fees. After the call I was concerned and went directly to the nearest MTN. At this point a lady helped me and reassured me that I do not have to worry because they just added more data. My intuition told me to go back the next day where another guy told me my contract had been migrated to the gold package! I asked him to stop the process and to please help me because I did not ask to be moved to another plan and that I want to stick to my original plan. All he said was that there was NOTHING he could do and was also really rude about it. He then told me to call Mobile Plus who just told me they would escalate my case. I cannot afford to pay more for my phone contract! If I could I would have signed up for a better contract when I bought my phone! I am highly disgusted. How can MTN allow this? Now there is nothing I can do or it will affect my credit score. I am beyond upset with MTN and most of all Mobile Plus for ****ming customers. I do not recommend doing business with any of these service providers.