Huawei P30
Android 9.0
1 Find "Call forwarding"
Press the phone icon.
Press the menu icon.
Press Settings.
Press Call forwarding.
2 Divert calls to voicemail
Press the required divert type.
Key in 707 and press ENABLE.
707
3 Return to the home screen
Slide your finger upwards starting from the bottom of the screen to return to the home screen.