Vodacom dishonoring warranty on handset bad servic

I was excited to get my new Samsung Galaxy S6 Edge when they were first launched, however my excitement is now long forgotten and I am convinced that Vodacom couldn't care less about their pathetic service and there commitments to customers. I have had the phone for +-4 months when I started losing reception. I could not receive calls anymore nor could I access the internet. I explained this in detail to the repair center consultant in Menlyn and had to take the phone back 4 times as this was not fixed. This is not a location issue as friends with the same phone do not experience the same problems. I have been patient and understanding to their poor reasons for, \the technician did not understand your query"or \""let us try again\"". I see it as very easy to solve. They have tried 4 times \""terribly unsuccessful\"" to fix the phone. I do not think they even did a QC afterwards. The phone has a 1 year warranty"