LG -G510 User Manual page 168

The barring service of all international outgoing calls except home
network.
The barring service of all incoming calls
The barring service of all incoming calls when roaming
You can cancel all barring service.
You can change the password for Call Barring Service.
You can restrict your outgoing calls to selected phone number. The
numbers are protected by your PIN2 code.
Press [Menu] in standby mode.
Press key for direct access or use
.
Scroll to highlight
Select PIN code by pressing
If the PIN 2 code is correct, you can view the following submenus.
: You can restrict your outgoing calls to selected phone
number.
: you can call without restricting phone number.
and
menu.
[Select].
to enter
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