MTN UPGRADE POOR SERVICE WRONG PRODUCT CANNOT BE REVERSED

I just wanted to upgrade my business Made to Share package that I had for the past 5 years, as it was due for an upgrade. The person assiting me in the MTN Middelburg Mall store, did not check what package I was on and downgraded my package. I used to be able to share my data and minutes with 10 Sim cards and now I can only share data which is not available on the new package to share. I am paying almost R3000 per month for this package plus now I have to buy R3000 data and airtime every week since 18 June 2024 as they cannot get my upgrade reversed. So, my R3000 per month package is now R3000 plus R12000 on additional airtime and data weekly. I have tried contacting customer care, Business complaints and all other means to get this sorted out but to no avail. The store should sort it out, but they claim to be waiting for MTN, and they get no feedback from them. How is this possible? What am I to do?