Explanation:
VoLTE Setting switch is gray and can't turn on VoLTE function. The interface prompts "VoLTE function of the located SIM card is temporarily not supported", indicating that VoLTE cannot be used in the network of the region or location, which does not mean that VoLTE is not supported by this mobile phone.
Note: Different MIUI version Settings have different details about the steps to enable VoLTE. Please refer to the phone setting steps for specific setting details.
