FNB *****S FROM PENSIONERS

My mom cancelled her credit card with FNB but every month they deducting money from her for the credit card my mom is a pensioner so she only gets a SASSA grant she went to the bank and spoke to the credit card devision over the phone they told her the card wasnt cancelled and that she will have to pay the outstanding amount before they can cancel it its really rediculous as it was the banks mistake and now they want a pensioner yo pay for it