Faulty/Damaged phone

I bought a brand new Sony Ericson M2 Aqua in January 2015 and within a space of 6 months I have brought my phone for repairs twice in July. In which case I had to bring the phone for repairs again within a week after It came back from the first repair. I wonder how did it then pass through the quality assessment check without the second fault being picked up? It clearly does not make sense that I am already experiencing such problems with this phone, which has proved to be no fault of my own. Clearly it's a factory fault, and if it is, why are you not replacing the phone with a new one? This phone is under warranty surely giving me a new phone should be a consideration!<br> <br> How can it be that I pay the full premiums yet I do not get the full enjoyment of the phone? I bought this phone for personal and business use and now I am being unfairly deprived of the full enjoyment and utilisation of it, as it has proven to be extremely faulty in so many ways! What drove me up the wall even more, is when I spoke to the Vodacom consultant he told me that the phone has a 2 year warranty to cover repairs, does that mean that we have to be sold faulty phones? Clearly that is not value for money!