Vodacom: The poorest customer service ever!

I ordered a new iPhone8 as part of an upgrade in January. After struggling to hear anything in slightly noisy environments I contacted Vodacom again to have the phone fixed or exchanged. RAM couriers collected the phone from me on 21 February. After hearing nothing from Vodacom for a week I followed up. The response was that the phone had arrived at the warehouse but had not been checked into the warehouse. The agent would log a call and have this done whereafter the process could start. A week later I again phoned with the same story: the phone had arrived at the warehouse but had not been checked into the warehouse. This has happened every week since and is still the status today. I am paying for a new phone but I have not had this phone for about a month now. Nothing I do seems to be able to get me anywhere. All I would like is to either: 1) Have the phone fixed; or 2) Have it exchanged; or 3) Have the upgrade cancelled and my money returned. If none of the above can be done I would be happy to simply have the Vodacom contract cancelled. This is the poorest customer service I have ever experienced! No one at Vodacom wants to take ownership and responsibility to address my problem but they are happy to continue taking my money!