why cant i have volte in my htc desire 828?

[AC Question]

i have an htc 828 dual sim.i searched and found that by dialing *#*#4636#*#* , entering phone settings we can activate volte..but i cant see any volte related settings there.LTE is working properly.the os is 5.1.1..it is not updated to latest version.. dose my phone support volte without rooting or any 3ed party apps? how can i activate it....?

 

[Mk1983]

Bhai, mere paas bhi yehi phone hai aur maine bhi bahut search kiya, desire hardware, aur band ke hisab se vo lte compeitable hai but software nahi hai, ab dekho htc wale vo lte support software provide karwate hai ya nahi, kal maine ek friend ko vivo ka lte phone dilwaya vivo jaisi tuchhi co. Ne bhi apne customer ko vo lte ki update de di hai usme maine software update kiya aur reliance jio chal gaya, htc jaise badi co. Ne abhi tak koi bhi update nahi di hai pata nahi saale aage denge bhi ya nahi denge. Kisi bhai ko kuch puchna hai to mera mobile no. Hai- 09354195415