voLTE settings for any phone

hlo everyone,VoLTE stands for voice our LTE is rullingout from past few months but some of our friends unable to activate volte in phone so there is a trick to activate volte
1. check ur phone is 4g or not, follow steps

>Visit imei.info .
>Then open the dialer of your smartphone and dial *#06# .
>This will give you the Imei of your phone .
>Now input the imei number in The imei.info website . And this will tell you if your smartphone is 4G compatible to make VoLTE calls or not . 
                             OR
The other way to check is simple going in the cellular networks of your smartphone and checking if there is a LTE network option available . 
The guide to activate volte call on any android mobile requires the below mentioned android versions 

2. how activate volte >

>First of all Open the Dialer of your          smrttphone Now dial *#*#4636#*#*.
>After Dialing the above number you will see the phone information .
>Now in the options there will be a option to activate LTE services , just enable that .
>After enabling go to the Cellular Network Settings
>Now enable Enable Enhanced 4G LTE Mode .
>After Enabling make a Reboot of your smartphone .

NOTE:
After Enabling the 4G volte you may notice slight difference in the battery backup of your smartphone .

If still volte not enabled then remove your both sim from phone reboot than put 4g sim in phone reboot again and then put another sim and reboot sometimes this trick work