Sony Xperia

I don't know how many more times I need to complain before something gets done. All I get is empty promises from the service centre at ***. Today I collected my phone from Vodacom repairs for the fourth time only to be told that Sony Service (SSS) found no faults on the phone and that a software update was done. Surely if one is taking a device in for the fourth time for the same problem there is a fault. Why do I have to keep taking my phone in for repairs and be totally inconvenienced? What is it going to take to get a new device? How many more times must I take my phone in for the same problem before something is done about it? I am not impressed with the service that I have received from Sony. This is the very last time that I ever get a Sony phone My phone isn't even 7 months old yet and I have only had problems with it. I will keep complaining until I get the response that I am looking for . A NEW PHONE SONY.. A NEW PHONE!!!.