Sim Swop done - still no Service

I got ****** for my handset, store and call center could not assist with sim swop. After a week i managed to get a new sim. I was told sim swop was done . 4 days still waiting for my sim to be activated. No one @ the credit vetting or the call center is taking responsibility for the call and no 1 wants to HELP .. so what do we a customers do. Really the service we are receiving is Terrible.