Have you tried restarting your phone? you can also try powering it down, taking out battery and sim card and reinserting it making sure its inserted snugly and correctly.
Also maybe your mobile network settings have been messed with. go to menu> setting> more settings> mobile networks> network modes> make sure GSM/WDCMA (auto mode) is selected.
if all this fails call CC, you might have either a bad radio or bad sim card.
Have you tried wiping your cache? I'm assuming you used to have service and this is a recent problem.
Wipe cache partition to clear system memory
If the phone is not working correctly, you may need to reset it. Whereas a hard reset deletes all your information, clearing the system cache does not erase any personal data or settings.
To wipe the cache partition, follow these steps:
- Turn off the device.
- Press and hold these three buttons at the same time: Volume Up key, Home key, andPower key.
- When the phone vibrates, let go of the Power key but continue to press and hold the Volume Up key and the Homekey.
- When the Android System Recovery screen appears, let go of the Volume Up and Home keys.
- Press the Volume Down key to highlight wipe cache partition.
- Press the Power key to select and wipe the cache partition.
- After the wipe is finished, with reboot system now highlighted, press the Power key to restart the phone.
Glad to see that it is back to working, even if just by random
Next time this happens, I suggest trying to put your SIM in another device to see if it duplicates, this will help us determine if it is an issue with the phone itself!
Thank you for visiting our community and have a beautiful day!