HTC India — Htc 828 dual mobile

Address:

Ratlam, Madhya Pradesh, 457001

Sir i have htc 828 dual sim mobile it is a lte mobile
Please update it in vlte. We are getting to much problem in voice in using lte
And i have also problem in bettery my go down in only 2 hour what should i do
There is inbuilt bettery how can i use it. Please try to resolve my problem soon
My phone is under warrenty please suggest me about both the problem
Thanks