MTN Promotions Are A Lie

I received an sms on the 5th of June 2018 from MTN Direct promoting an iPhone 8 on the Made For Me M package for R629 a month. If I did the upgrade during the month of June, I would get 2 GB of additional data every month. I did the upgrade on the same day I received the sms. The person who helped me said that the new contract will be effective immediately which it was. The additional 2GB data would be effective within a week after I gave him the promotion code. It's been a month since I upgraded and I still have not received the additional 2GB data, even after calling MTN Direct twice since I upgraded. Clearly this promotion is a BLATANT LIE and I do not want to support a company for 24 months if they are going to lie to me. Kindly cancel my contract and collect your phone.