cancellation of Blue Bean Card

Early in February i went into the branch to cancel the Blue Bean card. I asked for a settlement and paid the total amount. In March I received an SMS stating I owed an amount . I went back to the branch and they called the Blue Bean division and asked what the charges were and why the card was not cancelled. The consultant checked that the account was paid in full , Blue Bean said that it was the interest which I agreed to pay and she also called the insurance to cancel accordingly and she personally shredded the card and assured me that no charges will be billed again. However yesterday 20/05/15 I received a SMS adivsing me that I owe an amount again. What is so difficult to cancel the card once all monies owing has been paid and a request was given to cancell the card . This is ridiculous what does it take to cancell the card - i have also laid a complaint to the Banking Ombudsman hoping that this issue will be resolved. Bad Bad service from Standard Bank - GOING FORWARD think again