MTN - Useless Service As Usual

I have been with MTN for about 8 years and on the same package for the entire time. This month they decided to not upload the 500Mb of data that I have been getting for the last 8 years. I called and they said it shows that I am not entitled to any data. How is that even possible? And yet I am being charged the same amount I have been for the the last few years since my contract expired and I moved to a month to month basis. I call, and I get told the same thing - the salesmen has to escalate my issue - I then get a reference number for the call, and a few hours later I get an SMS to say the issue has been resolved and that my reference number is closed. I dont get it MTN - you want our money but are not prepared to provide the services??? PLEASE LOAD THE DATA ONTO MY ACCOUNT SO I CAN WORK. I am not prepared to go and buy a data bundle when I have already paid for one!!!!!!!!