Telkom should just close, they don't care!!!

I have a problem with telkom. I've been in a dispute with them for 14 months and they just don't care about their customers. To cut the story short I had an account with telkom and after 14 months I decided to pay the account even though I wasn't supposed to pay it because their account was affecting my credit record. After I paid them, now they won't give me a paid up letter. Now I'm in a fight with telkom for a simple paid-up letter. It's been 2 months now they don't want to give me the letter. I sent proof of payment to 3 of their consultants but they are just not issuing me with that letter so I can clear my name and credit record. I've reported them to ncr but still they just say they are busy solving the problem but I'm not getting any help.