Unable to do a Sim Swap??

I have been trying to do a sim swap since Sunday, I went through to a MTN store in Kempton park I purchased the sim card and the consultant said I need to contact 173 to do the sim swap. I get home and I try that however I am unable to as my number shows that its a contact, however this was changed a while ago to prepaid? <br> <br> I call the Pre-paid department and I get referred to the contract department, when I contact the contract Department and I get referred back to pre-paid department as it shows as a prepaid.<br> <br> No one seems to be able to assist me?? All I want to do is do a sim swap I get referred to go to a store and the store refers me to the call centre? What should I do? No body seems to know what or how to fix my contract!<br>