Customer Service department is absolutley hopeless

For the last 4 month's I have been receiving SMS's from MTN on a daily basis, to a number of mine that I do not use anymore. They are promotional and/or discount offers from MTN. I complained to them, and recieved a reply from Sheethal Bahgoo from their Customer Service Department, saying these SMS's are warnings that if I do not re-charge and make a call, the number will be de-activated. Come on Sheethal, how can you in all honesty say that these promotions/discounts are warnings?? You have my eamil address, send me your number and I will forward them to you. You can't even be bothered to reply to my email. HOWS THAT FOR CUSTOMER SERVICE? Please de-activate this number, then the messages will stop.