China Telecom(CHN-CT) is providing VoLTE service, and my SIM had applied VoLTE service, VoLTE Switch is always ON, this phone is always in service area，But No HD Icon, and can't registry to VoLTE IMS server. It seems nokia have to issue carrier VoLTE config file(mbn file?) OTA to full support this feature. So please Engineering team add it, thanks.
Sorry for my poor English!