i can't  use volte  features  im my Mobile the mobile network  section in there  volte  enable option  is missing    .   so  immediately  solve the issue  i can't  use   mobile  data while  calling    the mobile network   changing  4G to 2G coverage 

I'm in India but i bought my phone soudi arebia ,How to enable voLTE in my phone? My phone is GALAXY A6,Model number SM-A600F.and indian  firmware not available in  sammobile  website   pls  helpme     i need volte in  my mobile .  or   pls   giveme ...