Refund

I have contracts with Telkom I have been paying cash and was not aware that I have been charged R270 for every returned debit order. Nobody told me about that and since we are not receiving detailed statements I was only told by a consultant who said I must come back so that she can dispute for me. When I went back they gave me a number to call the lady told me there's nothing they can do about it. I've been paying cash for more than a year. I want my money back because the y always debit after I have paid. Please help. My number is ***