Bad for business

I had 2 accounts with SSDA, of which I paid both in full after they confirmed in an email the amounts. To date I only received 1 paid up letter. I call and Email them daily and they keep on telling me they are waiting on Cell C for the letter. When I called Cell c, they told me there is an outstanding balance. SSDA is now not responding to any emails from myself or Cell C. And this paid up letter is urgent and it's more than a month that om waiting. There service is BAD