Vodacom not responsive to closing account

I have been trying since July 2019 to close an account with Vodacom. Account was fully settled and confirmation received that my balance is R0.00, however based on a credit report the account is still open and shows that I owe then R729.00. How can this be possible? I have again requested that the account be closed. I can see they have read my emails but I still don't get a response. This is just not acceptable!!