Delayed service

I have finished paying my account off and have been requesting a paid up letter multiple times. I have two different case numbers which I haven’t received a response on either. They sent automated responses that they will respond in 48hours and they haven’t. I have been calling customer care for over a week now and still haven’t received my paid up letter. It’s quiet ridiculous that cell c takes so much time to provide a paid up letter. The consultants say they are gonna put up a notice for the matter to be attended but they don’t.