Bad service, and dishonesty

I will like to lay a camplain about FOSCHINI, I had an account with them and paid off their account and they still an extra amount after that, I paid the amount they requested and requested them to close my account, Then a guy from their customer service named Edwin sent me a letter stating that my account is being closed, but still again this month they are sending me statements saying I have an outstanding balance that I need to pay them. I am really not happy with their service because even my last contact with them the lady in one of their stores IN JOHANNESBURG KIDS STORE said she is doing me a favor by assisting me with calling the customer care service center. I will not and I am not willing to pay any extra fees after requesting them to close the account and settling twice ?