Bad customer service

On 2 July 2024 I received a call from Vodacom, informing me that I’m due for an upgrade. We concluded the “upgrade”. A few days later, I accesed the Vodacom app to review my contact. I was shocked to discover that the agent did not do an upgrade but instead added a new contract. I called Vodacom and they listened to the recording and then advised that they will collect the router and close the new contract. It’s been back and forth since July and Vodacom has not collected the router and they are still billing me. When I call they blame the courier guys and have no idea why it hasn’t been collected. This is messing up my credit record because on the ClearScore app my Vodacom monthly payment has gone up.