Destroying credit reputations!

You know when you finally manage to pay up and finish a cellphone contract, you get the feeling of relief, joy and a certain amount of accomplishment. However going to apply for credit at the bank and finding out that you are in arrears with the account that you finished is really the worst feeling ever. I went to the Cell C store in Westgate mall mitchells plain, and all they could advise me is that the account is indeed closed and the number is on prepaid. I asked how i can get this resolved and they advised that i should call client care to obtain a paid up letter that i would have to email to the credit bureaus. I did this on 14 December 2020 and was told that it would take 48hours. After waiting on the letter for weeks, i decided to call them again, and i was told that i have to wait as my matter is still pending. I have paid Cell C why is my life being ruined by them, and why is a paid up letter this difficult to obtain.