Delayed Contract Cancellation and Paid-up letter

I have paid up my contract and sent in proof of the payment. I was told the contract will only end October. I received an SMS confirming my number is now on prepaid. When I called in today requesting for a paid-up letter Sanele transferred me to a very impatient lady in the cancellations department. All I need from Vodacom is a paid-up letter that my contract is paid up it's that simple. I was told there's an outstanding amount I need to pay of R 150.74 which I have just done. please send the letter to ***