MTN did not inform client of loss during contract change, and does not respond to requests

After being really impressed that MTN contacted me to help me upgrade my contract, I was shocked to find out that my 40GB of data that I still had on my previous contract was missing. Upon contacting MTN they were happy to assist, and they told me that the sales consultant should have told me that the data will be lost. I told them that this was not the case, and they said that they will escalate the issue and listen to the conversation. I waited a while and followed up, to be told that I will be contacted shortly, and that the issue had been "resolved". I waited a bit more and contacted again, only to be told that the person who has "resolved" my issue is busy, and will be contacting me later that day. I am still waiting. Please give me my 40GB back, or a cash refund.