Debiting a child's account

Unfortunately I can't give no stars... I have a adisional savings account linked to my account that n manage for a child,. Without authorization FNB has loaded a debit order onto this account for something I don't even know what it is, when I call to sort this out I don't get through to anyone. And now half of a child's maintanince money is gone. This is disgusting making disisions on behalf of me without my consent. So much for POPI Act.