Took a data deal but no data allocated

Good Day I recently purchased a new Samsung A3 phone from Takealot. The deal was supposed to be a 1.5Gb data card to be used for a period of 12 months. I received the card with the phone and went to Vodacom Killarney Mall to Rica the sim. There was no data allocation on the card. I contacted Takealot and they received an email what USSD string to enter. This as well did not work. String entered does not exist. They are now say they are not responsible for the promotion as Vodacom are running it. I know would like to know what I must do about this. I only bought the phone from Takealot because of this promotion. If there was no promotion I would of bought it from any other reputable store that sells the model. I am hoping this can be resolved.