Nedbank - Lack of Clarity and Communication - General lack of Customer Support

Nedbank refunded me on a fully paid up account with a paid up letter from an account I opened years ago and subsequently settled. And according to my last communication, the account was closed. Today, while trying to link my NEW Greenbacks card to my banking app, I was advised of an adverse account listing on my banking profile. I phoned the call centre, who explained that they over-refunded in DECEMBER 2021. How is this my problem? I had no visibility of the error. Furthermore - why is there a backlog of over an hour at any of the branches in the North-Western suburbs? It is impossible to get anyone to help you as a customer! From the general demeanour of other banking clients I have spoken to (in branch), I am sure I am not the only person dealing with this kind of poor service and triangulation of communication.