Debit of full amount 2 months after downgrading

I had downgraded my DSTV package from Premium to Compact in July and my debit order is still going through for the full amount, 2 months in a row. I called the call centre and my call was conveniently cut while they were dealing with my query. They have my cellphone details on record, yet the consultant has not made any attempt to contact me. I cannot manage my monthly budget with DSTV not fulfilling my request. I will consider cancelling my subscription altogether in order to manage my month end expenses, seeing that Multichoice cannot respect my request.