I am in India, bought the phone last Diwali 11-NOV-2015, from Reliance Digital, Sarjapur road, Bangalore, with an extended warranty of 1 year (by Reliance)

Same story as with everyone else. After exactly 13 months of use, the phone died on me. It would wake up once in a day after repeated attempts to switch it on.

I put it on a polythene ice wrap, was able to switch it on, delete some apps n videos. But it doesn't stay alive for more than 2 mins. There is no Sound while booting, although rest of the sounds work when the phone comes alive.

There is atleast 2-3 GB space available on ROM. Not sure whether the motherboard has gone bad, or if there's a lose connection, or it's the OS. I remember i upgraded to Marshmallow as soon as the phone showed me that Marshmallow upgrade was available, which was some 6 months back.

Had to take out the SIM. I never put an SD card inside.

Can somebody suggest if I need to :

1) Replace the Motherboard, OR

2) Downgrade from Marshmallow to Lollipop, OR

3) Go for a Factory Reset ?