My Mobile phone is factory Unlocked Sony Xperia XZ Model F8331 (US) Single Sim.
I reside in India. I am using Jio4G sim and network. The problem is Jio is not allowing make and receive calls and messages unless Jio4GVoice application is installed. To avoid using this application the phone must be capable of VoLTE. So I tried by using:
*#*#4636#*#* to enable VoLTE
The following options are displayed:
Mobile radio power this is existing (enabled)
VoLTE provisioned Not enabled and tried to enable
Video calling provisioned disabled
Wi-Fi calling provisioned disabled
When I tried to change to "VoLTE Provisioned" an error message is displayed
SMSC: Update error
I don't know what to do to solve this problem
