Find "Call forwarding"
Press the phone icon.
Press the menu icon.
Press Settings.
Press Voice Call.
Press Call forwarding.
Select divert type
The current settings are displayed.
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Press one of the following options:
Always forward
Always forward
Forward when busy
Forward when unanswered
Forward when unreachable
Divert calls to voicemail
Key in (prefix) 5 (your phone number) and press Enable.
Return to the home screen
Press the home icon to return to the home screen.