MTN DROPS THE BALL - VERY FRUSTRATED

I called the MTN customers line and after 22 attempts I got hold of somebody. I asked about upgrading as my phone was due for an upgrade. They told me that I can do it in store. I spoke to the Retention department and they said that if I upgrade they will give me R1500 free minutes. I went to upgrade to a new phone and Caleigh Dalbok assisted me. She upgraded me to a R399 per month contract and it also stated that I will get R1500 airtime. NONE OF THIS HAS HAPPENED. MTN charged me R500 for a few months then R549 and so it went on. Months passed, I have been ********** by R100 or R150 a month plus I have never received my R1500 airtime? I tried calling 808 to no avail. at first. After attempt 43 I got a consultant that apologised to me and said that she will set this straight. STILL NOTHING HAS HAPPENED. Asked Caleigh from MTN Hemingways to help as she sold the contract. 1) She stated that she has given up on this as she can not get through to head office. 2) After going to her the third time she said that she will follow up. 3) She came back to my 14th May saying A) MTN is at fault as they are still charging me for my old phone B) Retention will follow up the R1500 STILL NO ACTION