2017 Black Friday Was a Lie

During the 2017 Black Friday special on the 27 of November, I went to the Woodmead MTN store to sign up for the 50GB special of R299. I got approved and on Thursday 30 November 2017, I went to collect the simcard. The issue started when the 50GB was supposed to be loaded on my sim. It didn't happen, infact I got 10GB day and 20 night. I called MTN to fix this and I ended up getting 20 day and 20 night which means I got a total of 40GB and missing 10GB day. I called them to try and fix this and the kept giving me new reference numbers. My last reference number was 1- ********** 6364. When I call and give it to them they say its still under investigation after more than 21 days. The frustrating part is MTN kept sending sms that my account will be suspended if I do not pay it. Why am I paying the full amount while they did not give me the full package we agreed upon. It is my first time joining MTN and I have to say, I am not impressed with them at all. Can you please fix this and provide me with my data because if this is not done I would have to cancel this because this is not what I signed up for.