I was just in England and able to use wifi the entire time. However, after a day or so, I had no phone service at all--in fact, there was an "x" above the bars. Error message says: Call settings error: Network or SIM card error." Now I'm back in the US, but I still can't use my phone. I have the network mode set for automatic, and the network operator too. If I take it off automatic slection and try to select T-Mobile as a network operator, I get the message "Unable to connect to this network at this time. Try again later." The pull-down menu still says "(no service)." I hope somebody can help! Thanks.
Take a look at Signal troubleshooting: Android, this will help you work towards diagnosing and resolving your issue.
Thanks! Because I was feeling a bit desperate for an immediate reply, I tried online chat. Popping out the battery and replacing it did the trick--which was the suggestion on the link you sent, so that was exactly right. What a relief.
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