Panasonic smartphone — Battery backup

Address:

Bhopal, Madhya Pradesh, 462023

I have purchase the phone 4 days earlier but my battery is not giving me the backup of at least 06 hours. So i request u to kindly look into the matter of replacing this smartphone, as soon as possible, otherwise i will directly complain it to the head office.
I have panasonic eluga i2.
If you are not able to replace if kindly make sure that the battery backup of this phone will last longer.

Thanking you,
Panasonic user