NO SERVICE

Hi. I have an Apple Iphone 5S that I had a prepaid Vodacom sim in that worked perfectly. All of a sudden it displayed NO SERVICE so i did a sim swop and moved my contract number to the iphone and got a new sim. Still NO SERVICE. Went into Vodacom Pavillion and they said it is an iphone problem. Went into IStore and they said it's a Vodacom problem. I have reloaded software. I've reset network settings. Manually searched for the carrier etc etc etc. Now sitting with an IPhone that says no service. I phoned 082111 last week and everyone I've spoken to tells me to to do everything I've done ten times over. Phoned them back at 4 pm yesterday and was told I can't speak to a technician I must wait for someone to phone me. Then told me they have sms'd me. Asked where? They give me my number that doesn't work!!! IStore tried a telkom sim...worked perfectly. Tried a MTN sim and worked fine. Tried another Vodacom sim and didnt work. All the Vodacom sims work perfectly in other phones. I am so beyond irritated with this. I have kids who need to get hold of me. Please can someone sort this out urgently!