MTN Sim Swop unsuccessful.

I did a sim swop with MTN on 02 December 2023, it is now 09 December 2023 and it has been 7 days since I did the sim swop and my sim card is still not working. The store managers at MTN Southgate and MTN The Glen have no clue what to do besides escalate the matter which they have been doing for the past 6 days to no avail. I have no idea what to do at this moment, their customer care is the most useless customer care I have ever come across. They can't even cancel the contract now I am paying for no service.