Poor customer service / debited twice.

I called to change my debit order details early December and I was advised that because it is closer to my debit order date, the debit order will only be effective in January therefore I have to make a EFT for December. I made the payment and Telkom still debited my account for the same month. Sent countless emails to have one payment reversed but no one is getting back to me :-( The level of poor customer service is on 100!!