Paid up letter

I am in utter disgust that I write this unfortunate communique to you. As I have been requesting for a paid up letter for half the year already but I feel like I'm speaking to a wall, I have been calling for numerous times and being taken from pillar to post and being handed over again for non payment which I have paid. My question is when will I ever be able to carry on with my life and apply for a house that I have been applying for but Cell c seems to love distroying my credit. I feel this is unfair that a credible institution like yourself can find itself wanting, when it primary role is to provide a dependable and trustworthy service. May I please get assistance.......