Huawei P40 Lite
It's not possible to make voice calls
Solution 2 of 11: The selected network mode isn't available
There may be different network modes available depending on where you are. The network mode influences the data speeds your phone can achieve.
Press Settings.
Press Mobile network.
Press Mobile data.
Press Preferred network mode.
Press the required network mode.
Slide your finger upwards starting from the bottom of the screen to return to the home screen.