Bad service

Upgrade was **********ly done on my data contract. Initially I was not informed that I had to open a case of ***** with saps. This was after calling the call centre twice. I was promised the matter would be investigated and I would get feedback. To date no one has called me back. The ***** department promised to call me back in two days. This was never done. When I called the ***** department ten days later I was not given the answers I am looking for. Sent an email to customer services but have not received any feedback. Am waiting for MTN to tell me what is going on. Am being billed for data usage although I should not be.