Nedbank unable to provide paid up letter as promised

I have recently settled my personal loan and asked for paid up letter and was told will receive within 2 days but to my surprise when I called to follow up I couldn't get hold of anyone as the lines go on mute and the time I get hold of someone they talk over me without listening to urgency or concern and this time told it will take 10 working days for a paid up letter. I need to get my paid up letter as like yesterday so I can close my other accounts and noone at Nedbank takes this matter seriously. It's very frustrating dealing with Nedbank.