Bill Dispute with Starhub

I rang Starhub in June 2010 after being billed $70+ for the month and not $46 as it supposed to be. They explained that because my package had not yet been updated. They reassured me there was no worries as the balance would have to be refunded in the following month (July). Come July there was no refund and worse still, the bill was even higher ($75+), and they had charged my credit card without providing an itemized account for each costing! I called and the staff member informed me that the system was being upgraded and that delays would be inevitable. However, I should be refunded by the following month (August). I requested him to contact the ‘Standard Chartered Bank’ and clarify the account. He agreed to call me back when the matter was resolved. But I did not receive any call from him until today, which is 10 days later. He stated that his name was ‘Moziz’ (or something which sounds like that). He was very rude and insisted that no further progress could be made until I first pay the bill. Totally different from our previous agreement! I refused and reminded him that it was illegal to ask people to pay without a bill. I realised that he was not going to be able to help me and so I requested to talk to his manager. He said it would not be possible. His attitude was extremely poor during the whole conversation. The company’s failure to resolve the situation is a poor reflection on the organization and its employees.
P.S. This problem has been solved in Jan 2011.