Cell C and Paid Up Letter

My account with Cell C Fibre was paid up and the department sent me a paid up letter. However, I moved not long after that and was involved in an armed ******* where most of my household contents and vehicle was ******. My email account that I had for 9 years was blocked. I have contacted CellC 4 times this week and asked for the paid up letter to be sent to me as it still reflects on my credit report that my account is open and that I owe them money. When I phoned this week, I am in credit and they owe me money. To obtain a paid up letter from Cell C seems to be a very difficult thing for their staff in finance to do