Credit Card

I got a credit card from African Bank in 2011 from African Bank. The deal was that I'll pay R510 every month irrespective of whether I have used it or not. The agreement stated that I should inform the bank if I loose my job or get retrenched. I lost my job in 2012 and my account was up to date. I personally submitted all the documents to Roodepoort African bank brunch and a week later I receive a confirmation that the account has been paid. Three month later I received a call from African Bank demanding payment of R510,I told the caller my story and she told me that the insurance paid half. I am still getting SMS's demanding payment and I don't understand why the insurance paid half while my account was up to date.