Vodacom profile affecting my credit bureau profile and contract application

I cancelled my contract last year April, and went to Pre-Paid. I have been trying to apply for a new contract since March this year (first online, then at the iStore and finally at the Vodacom store in Canal Walk), and each time have had my application cancelled with zero communication.

I then gave up with Vodacom, and tried with MTN, who gave me a straight answer that Vodacom has erroneously flagged me with a Credit Bureau and as such this has affected even my MTN application.

I have checked on Transunion and my credit score is exemplary, so this confusing and frustrating and nobody at Vodacom seems to be able to give me a clear answer (and I am pretty tired of dealing with bots or broken online-chats). I have also noticed that other customers have had a similar issue when moving between contract-prepaid-contract in the past, as Vodacom fails to settle/mark the account as closed.

I would appreciate someone senior or at least knowledgeable contacting me.