Nedbank bad FICA system upgrade

Nedbank has gone on a FICA upgrade on accounts. Unfortunately Nedbank cannot upgrade my child’s FICA and has therefore blocked all access to the account. I have went several times into the bank and made calls to sort it out but nothing happens. I even went as far as requesting to close the account but they also refuse to close the account. My child has not been able to access the account or even use the money in the account for almost a month now, Nedbank is not interested in solving this problem and I honestly don’t know what to do further. I have experienced good service from Nedbank but they are the worst in solving client problems. At this rate I just want the money and move to another bank. How can I be unable to close an account that I opened in The bank. I am very dissatisfied and unhappy client.