Zte A39 User Manual page 52

Select On/Off to enable or disable the handset lock protection; select Change
Code to set a new handset lock code.
Note: The default handset lock code is 1234.
Network Call Bar: You can set any combination of the following call restriction
option to improve security level. Please contact with the network service provider
for detailed use. The network service provider provides a 4-digit network password
to enable your call restrictions.
International Calls: Bar all outgoing international calls.
All Except Home: Bar international calls except local call.
Incoming Calls: Bar all incoming calls.
Incoming if Abroad: Bar all incoming calls when roaming abroad.
Outgoing Calls: Bar all outgoing calls.
After choosing one of the above options, select Select to restrict any of the
following services:
All Services: Restrict incoming calls, voice calls and short messages.
Voice Calls: Only restrict voice calls.
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