Cellc and blake & ass- Paid up letter

Cellc listed me with this company. They called and I made an arrangement to pay them back monthly.. beginning of March I decided to pay off the whole amount, after paying it off i called the lawyers to request my paid up letter to which they said will take 7-14working days?on the 14th day I called to find out why I hadnt received the letter, I was then informed that they have made numerous follow ups with their head office and they will make another one. I then told the agent that I was not happy with her following up because it clearly was not effective! She said there was nothing she could do and she doesnt know how long they will take to respond. I asked the lady if I could speak to a supervisor... she put me on hold for quite sometime then returned to tell me that the supervisor was not available and that she would take my details and get her to call me back. To this day I have not received a call back. How hard can it be to draft a letter? Since they deal with collections surely they have a template of the paid up letter and all they need to do is add my name in there? Iv honored my arrangements and paid of the debt but im still listed on ITC as owing! Cellc claims they cannot remove it until they get the paid up letter!! Why are they not liasing with one another to send the letter?? Its so unproffessional and such an inconvinience.