Does the tablet have active service with VzW? If so, have you tried turning off the tablet and removing the SIM card for a minute or so? Is mobile data turned on? The SIM card may have become corrupted; if so, you can replace it free at your local Corporate VzW store or by contacting Customer Service.
I apologize for this inconvenience. I know how important it is to have a working tablet. Let's work together on getting this resolved, when did this issue start? Have there been any recent changes to the device (software, apps, etc.)? Are you able to power on your tablet?
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