why my samsung s7 active doesn't support VOLTE RELIANCE JIO in india?

[Android Central Question]

Recently i bought asamsung s7 active from usa. i was very happy after the purchase but everything change when tried using Reliance jio 4G on my Samsung S7 active. Iam not able to make VOLTE calls on my device. I have two questions.
Q1- How can i use Volte on samsung s7 active with Reliance jio?

Q2- Can i flash samsung S7 Pre VOLTE enabled Indian firmware to my samsung s7 active? If it is possible please help.

 

[B. Diddy]

Welcome to Android Central! What's the exact model number of the phone?