I have problems making WiFi calls on my Huawei nova 5T

Press Settings.

Press Mobile network.

Press Mobile data.

Press Wi-Fi Calling below the required SIM.

Press the indicator next to 'Wi-Fi Calling' to turn the function on or off.

Press the Home key to return to the home screen.

Press Settings.

Press System & updates.

Press Software update. If a new software version is available, it's displayed. Follow the instructions on the screen to update the phone software.

Press and hold On/Off until your phone restarts.