Paid up account still reflecting on credit bureau

My account was paid off in August 2019. I have been trying to send emails requesting a paid up letter in order to update my credit bureau but no luck. It is impossible to get through to contracts department because I'm now on prepaid.

How does Vodacom keep updating my credit status when I no longer have an account with them, this has been going on for too long, Almost 12 months now.