NOT DOING THEIR WORK

I Called fnb a few days ago after I paid off my credit card that they must cancel, I spoke to the lady by the name of mandisa , she told me the ref number is my id , the credit card will close by will know in 7days its not existing anymore , but she advised notes and all are clear and will send to the correct department , this morning money goes out of credit card and I pay the balance to make it up to what I owe and I called the department again , was assisted by a lady did not get her name , asked her if the credit card is closed and she said no its not but its paid up , and asked if nothing shows I called she said no , I told her I called spoke to Mandisa and she said then Mandisa must then be the one that does it ,I want this credit card close , I don't want anything to do with fnb , just feel service is pathetic