F840- User Guide

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Troubleshooting
Network failure
● It is possible that the phone is located in a weak signal area, move it to place with
stronger coverage.
It is out of network service coverage
● SIM card is not valid, contact your network provider.
You have entered a number but the phone is not calling
● Make sure you have correctly pressed the button.
● Check call barring options. Verify that barring is disabled for the contact number.
● Check the fixed dialing setting is disabled.
● Check that the SIM card is under network coverage.
● Your network operator may be experiencing connection problems.
The call quality is poor
● Check volume.
● It is in a weak signal area, such as near tall buildings or in a basement. Move to a
location with better signal strength.
● Your network operator may be experiencing connection problems.
Your correspondent can not call you
● Make sure phone is turned on and connected to a network.
● Make sure SIM card is not locked.
● Check your phone is being covered by network
● Check that you have not set an incoming call barring.