Settled Account - Paid up Letter

I settled my account in July already. I continuously called in for a settlement letter. I was told there was no such account etc. Eventually I called Cape Town direct. I spoke to several individuals there as well. I was then told it takes upto 17 working days to receive a paid up letter for the account. It is now almost October and there has been no response. There's no response to emails either.

I have tried over the past week to call them several times and you are just kept on hold for more than 10 minutes at a time.

What would it take to get a response from your company.

SHAMIM