Phone worked only for a month

I've bought a Huawei G7 contract phone at Vodacom shop Hemmingway's mall in East London in October 2015, it was fully functional for only a month of November 2015, from December I haven't been receiving sms's and I am unable to send sms's for 3 months now, sometimes when the phone decides to receive sms's it will be sms's that have been sent a month ago. I have contacted Vodacom contact Centre and I was told at first it was a network issue, and then I was advised to take the phone to Vodacare shop, I finally left it for a day at Vodacare shop at Vincent on the 22/02/2016 which I was told everything is fine no faults have been detected from the phone, I can receive sms's when the simcard is inserted into the other device. When I called the Contact centre again to give them feedback I've been advised to visit Vodacom shop and leave it for repairs. I visited the Vodacom shop today at beacon bay and I was told to visit vodacare shop again. My life depends on this phone I cant access even my internet banking, please help.