Vodacom changing details on Fibre account

When trying to phone about Fibre not working, Vodacom does not have the correct address on the system, I cannot pass the security questions, because my number keeps changing on the Vodacom System?

Whenever I call in, they just say we will update the info, that is not acceptable, who is giving Vodacom permission to change details on accounts without contacting the client? They do not have the correct number or address listed. How to resolve this issue?