I bought a Sony Xperia M4 Aqua on 11th July this year. Worked well for few days but on 2nd September it suddenly stopped functioning. That can happen but the service afterwards was no longer what Sony used to be. No wonder it is going down the drain.
The dealer sent me to a service centre in Nehru Place(He gave us the wrong address) The centre said it is a manufacturing defect. I guess they may repair it in a few months as I have yet to hear from them. For me never gain SONY