Bad customer service

In Jan I paid my dstv account using an incorrect reference number and I called them and emailed them to explain what happened and provided proof of payment. All seemed good and well and the last communication was the money will be allocated to my account and I will pay the difference. Now that is Close to month end and I want to pay the difference it's was not updated and when I called them yesterday the lady made me hold for more than an hour and I knew they where going to do that hence I had enough airtime and they dropped the call. How rude. Anyway I sent an email again to follow up and still nothing.