Charges after balance was paid

On the 14th of September i went on to my internet banking profile to retrieve my latest balance, we then proceeded to pay off the balance and we went in to the Vaal Mall branch where they informed me that there was R0 outstanding and that the card department will close the accounts, then when i phoned suddenly there was amounts outstanding, i have been with nedbank more than 10 years and never had such poor service, nowhere on the internet banking or statement does it say that you have to phone to get a balance, i think the ombudsman will agree this is totally unacceptable!! I will definetely change my bank'