Insurance claim

Good day My dad has a credit card with standard bank since 2004 (estimated year). He passed away last month and my mum went to the carnival mall standard bank and spoke to Cheryl the manager. She informed my mum that after 65 years of age the credit life insurance converts automatically to death insurance and we were suppose to still be paying for the insurance. After cheryl called the credit department she said that the insurance was cancelled in 2008 and was not converted to death insurance. We were not informed about any changes to the policy regarding the death insurance so with whos authorisation did they cancel and not add the death benefit. Why should my mum pay for the balance on the credit card when there is suppose to be death insurance added.automatically after the age of 65.