Not following orders

I had a account with nedbank as well as a cheque account for my 5 year old son. I used his account for my salary when I was still employed. I have cancelled all debit orders and asked to close the account at the branch a while back due to me being unemployed. The account has unneccesary fees now and the account was handed over. But orders to cancel it was not followed. Now I get calls that they want to speak to my 5 year old son to ask him when he is going to make payment. Really. I explain to them that he is underage and that I am his mom but they just drop the phone and don't want to heat anything. Can this account now be closed if I ask on hellopeter or what because if I go into the branch they don't follow requests. This is ridiculous. Surely you can see he is a minor. Sort your mess out.