Billing Errors

I called into Autopage Cellular to Query why my bill was unusually high. The consultant who assisted me agreed that something was wrong with my allocation of data or minutes and said she had logged a query. I still haven't heard back from them in two weeks. I called today to query the same thing and Bongani in the customer service call centre tells me there is nothing wrong with my account. No one can give me a straight answer and now they are going to expect me to pay another month( I paid my last bill in full regardless of the pending query expecting a refund) with all these extra charges. They really are a joke and couldn't be bothered about their clients. This isn't the first time I have had problems with Autopage. I definitely wont be renewing my contract with them or referring friends to them either. Why cant they just check what the problem is, fix it and give me my refund so that I don't spend another month out of pocket because of their mistakes.