Standard Bank helps themselves to unauthorised debit orders

Its been weeks now that I am trying to get an answer from Standard Bank Vehicle Asset Finance regarding the settlement of my vehicle, I settled the vehicle and still they debit my account, no one responded to over 50 emails sent over almost a month .. no answer on their automated answering system and if you do get through they give you another number to call and wait for 20 mins listing to that ridiculous tune .. this is day l light *******, is this not theft if they take a debit off AFTER the zero balance was received. .. another month coming up and one entire month spend running after them to get a response. They DO not reply to emails and there is no direct number .. this is becoming highly frustrating that an institution such as Standard Bank can ignore their clients and ***** their money like this!!!