Snapdeal.com — Phone getting switch off, finger print sensor not working

Address:	Udham Singh Nagar, Uttarakhand, 263153
Website:	snapdeal

While using phone its getting off after 2-3 hours and when I use finger to unlock my phone through finger print sensor and then it's vibrates only but phone isn't open... this issue comes 2-3 times in a day.
Phone hang during operating the phone, I many times reset the phone but same problem comes.