Business contacted - I don't think so

Despite on my first complaint there was a very nice message and that the Manager would phone me. I have sent him a message via Hello Peter and to MTN Facebook page nothing has been done. In fact its got worse - Despite going into MTN la Lucia and paying R2000 in advance of a trip to Australia so I could make calls I arrived in Australia NO SERVICE. My husband has Vodacom and he was fine. The girl in La Lucia assured me prior to leaving that the settings on my phone and at MTN were all correct. I wish I could just cancel my contract and switch to Vodacom. I am going to look at the legality of terminating my contract based on lack of service.