Identity ***** risk(Possible POPIA Violation)

I have a savings account with Nedbank. Yesterday, I received a forwarded message from Rapula Khumalo stating that Nedbank called his ex-wife to inform her that she must come and close the savings account I had opened for their child as the funds in the account were withdrawn. The ex-wife went to one of your branches to close the account but when she got there, they told her that she cannot close the account since she is not the one that opened it. My issue is that the ex-wife was not listed as an alternative contact number yet she was informed about the transaction and account activity of an account that I opened. I need a thorough explanation of how this transpired as I believe my information was not handled according to your privacy terms and conditions.