You can block certain types of calls such as incoming calls when you're abroad.
Find " Call barring settings"
Slide your finger down the display starting from the top edge of your mobile phone.
Press the settings icon.
Press Call barring settings.
Select barring option
Press one of the following options:
Outgoing international roaming
Incoming calls when roaming
If you select Outgoing international roaming, no international calls can be made, but you can still call home when you're abroad. If you select Incoming calls when roaming, you can't receive incoming calls when you take your mobile phone abroad. Incoming calls will be rejected by the network and the call won't go through.
Activate or deactivate call barring
Key in your call barring password and press OK to activate or deactivate the function.
Return to the Home screen
Press the home icon to end the session and return to the Home screen.