VoLTE disappeared after updating m3 note

hi. I updated my meizu m3 note (m681h)to 6.7.4.11G beta , after that VoLTE option disappeared from the settings menu.

Meizu m3s

Downgrade, meizu firmwares are not perfect, this is a known problem for 6.7.11.4

Help me
Explain this
make form this bro…
http://aiomobilestuff.com/meizu-m3-note-mt6755-flash-files/
meizu m3 note flash with sp tool

Looks like your connection to Meizufans was lost, please wait while we try to reconnect.