Fed up with MTN Inexperienced Agents

I app**** for a new contract on Tuesday (17/12/2019) at Rosebank Mtn shop, this contract was to be used with my existing prepaid number. I received a device immediately but up to today ( 3 days later) my sim card is still not active. I have made calls to the call centre and I have been to the shop several times without any joy. The shop says they don't know what is happening with the line.Who am I to know if the service champions don't know. I'm so fed up and extremely inconvenienced.