If your device displays a “No Service” or an “Emergency Calls” only message, this would usually indicate that you are in a location with poor signal strength / limited network coverage.
As a further test however, we would recommend attempting to select a network manually –
1) Go to the main ‘Menu’ by pressing the top left button on the keypad.
2) Scroll down and select “Settings” (icon shows a picture of a wrench and two gears).
3) Select “Network Settings”.
4) Select “Network Selection”.
5) Change the search mode to “Manual” and wait while the phone searches for networks.
6) Choose a network from the list and (if the connection is successful) retest.
7) If this resolves the issue, please change the network search mode back to ‘Automatic’ when you travel to a new location.