LTE sim swap

I received a call from MTN saying that they would be delivering a free MTN LTE sim card to my house. I asked them what the benefits were and they said I would receive faster internet and get a 30gb free data bundle for switching to LTE which will be loaded automatically after I perform the sim swap and activate the sim card. I receieved the sim card and performed a sim swap because I wanted the free data bundle. When calling the service centre, they said that there is no free data bundle linked to my account and there's nothing they can do. I was told to wait 24 hours for it to be logged and try again, I called 2 days after because I still didn't get the data bundle and the consultant asked me to call back in 48 hours. I called back now and they're still telling me there's nothing they can do. I know it's a free data bundle but I was promised it and now they can't keep their promises.