Bad service

I did an upgrade with cell c recieved my phone on a Thursday 7/05/2015 with the phone came a nano sim card which on the delivery note said would be active within 24 hours. On friday after the 24 hours had gone by I called and was advised that I needed 2 call, ok that was understood however the agent then said they would log a case to get the correct department to call me back, I insisted that I would call the following day (Saturday) which I did as was advised that the department would be open I have since been calling abd I have bn passed from department to department yet my sim is still not active, I am still unable to use my phone and no one has called me back as was promised.... I would like this phone to b collected as I am unable to use it and am now fed up with having to call! I will stay with my current contract till it expires in July then cancell my contract with cell c and go to another network! I am a paying customer and for me not to be able to be provided with the service im entitled to is just utter ********