Help Auto restarting!

[arunsubbu]

Why my mobile gets auto restarting (even while I was in a call)! Is there any settings I have done by mistaken or due to an app update or OS update?

I'm so curious and so scared. Because in the last two days, it restarted some 5 times a day.

Please help. Do I need to claim for warranty?

Thanks,
Arun