I don't know why I'm so happy to tell (Lol) but it took like 10 days and around 10 times calling at the Zong helpline but yeah it was my lucky day today and I managed to enable VOLTE on my Zong number through the CSR, he asked me all the things which other folks told on this thread like my city, my phone model. Most of the CSRs did the same thing but ended up telling my that the service was in trial phase and was being provided to limited random numbers in limited areas of limited cities but this representative did something different and generated a service activation complaint, that CSR first checked that whether my phone model and my location was even eligible for volte and told me that both the things were a yes, I was eligible, then CSR told me that your request would be entertained and you would get a reply in 24 hours, I called the helpline at around 4:45 and in almost 2 hours I couldn't believe my eyes, I could see the Volte sign next to my signal bars in around 2 hours after I made the call, I even got a call from 0310 saying with a guy telling me he was from the complain dept and my request was initiated, asked me to check if my requested service was activated. So that was how I got Zong Volte activated on my number, I don't know why they aren't enabling it automatically to all users which have Volte supported phones but yeah if you want to get it manually activated its just pure luck with the CSR you get to talk to, I haven't tried making any calls yet because obviously almost no Zong users have Volte as of now but will let know everybody here the results if I find someone also using Zong Volte.