Total Lack of aftercare service

I did my upgrade at MTN Canal Walk on Saturday, 8 August. I was told that I would receive 20gigs of data with the upgrade. Just before leaving the store, I told the salesperson that I didn't receive the 20gigs as promised and he assured me that it would take up to 24hrs to receive it. By Monday, 10 August, I still had no data. I spoke to the salesperson again who assured me that he would escalate it to MTN. I waited and finally received a message that the query was logged. By Tuesday, I still had not received the data and asked him again and he assured me that i would have it within 48hrs. I then received an sms today at 11h07 saying I've been successfully been authenticated (for what I'm not sure), then at 14h00 another sms stating that my query has now been dealt with and it has been closed. Then at 14h02 another sms asking me to rate Busisiwe's handling of my query and the call with her. I never spoke to anyone from MTN today seeing as nobody returns my messages anymore and my calls aren't answered. Yet, when they wanted me to do my upgrade with them, my messages were responded to immediately and i was even called to ask when I would come in. But now that I need them to fix something, this is the service I receive. I'm disgusted that I have to call and send messages to MTN all the time with no resolution to my original query. I will definitely not be using MTN Canal walk branch again.