Depends on device. Example: in lavender VoLTE works, but shows no icon in statusbar. VoWiFi can be activated in settings but doesn't work at all because of missing MBN tool to change the profile.
Already tried. Doesn't work on lavender. After dialing a number it shows "deactivate flight mode or use wifi..."
Think lavender needs other profile in MBN tool.
there are still some types of devices missing the VoLTE symbol. Lavender too. Hope Xiaomi will fix this finally
On the other side this the new 21.1.13 rom is running fine until now
Lavender. Dirty flash. New version running for 1 and a half day. All fine until now. Only thing I'm missing is the VoLTE symbol in statusbar. But this problem already exist long time