Paid up letter not being provided

So once again I have to deal with extreme incompetence on the part of cell c. I have paid more than R8000 on an old account to settle in full. I have requested a paid up letter for the fourth time today as not a single person was able to correctly complete your internal processes to date. First case was closed stating that the account is not settled. Case number two closed as the agent apparently did not include my ID number. Third case was closed with comment line is active. Today I had to go through everything again. What I cannot understand is why I never receive a phone call or any correspondence before cases get closed, why would I request a paid up letter if I did not pay, and why would I request a paid up letter for an active line? Moreover how can a case even be submitted without all the information being properly captured. I asked to be transferred to a supervisor and was very conveniently cut off. I want this sorted today because I cannot wait another 48h business hours just to find out about the next error you made. This is really appauling service!!!