kEEP ON BILLING ACCOUNT AFTER CLOSING ACCONT

I rquested my blue bean accont to be closed years ago. Twice I paid in the confirmed aotstanding amount , twice it was not closed as costs went through after the settlement amount was given to me. Third time I paid in much more than was outstanding to close the account. Guess what - not closed monthly cost going through .Phoned again end of 2015 credit left was transferred to my account(not all money overpaid) with the confirmation that my account was closed . Low and behold I get threatning sms I will be constituting frau if I use the card again. I did not use the card for years and don't intend using it ever . I think Standard bank is committing ***** invoicing me monthly after I requested them numerous times to close the account and I did not owe anything on this card. I also was promised an e mail numerous times confirming that this account was closed. Attempting to speak to a senior person to sort my problem resulted to hours on the phone and ZERO results