Not Getting what was promised,,,

I am Sinethemba Gabada *** ID No. ***

The number I am complaining about is ***... I had done an upgrade at MTN Hemmingways in East London on this number for a Dell Laptop and the laptop was on special for R250 for 10GB which is 5 GB Data for day and 5GB for night but i am getting 2GB. I have just checked with MTN to find out what am i getting and they confirmed that my new contract offers 2GB... Please MTN attend to this...