Have you used the Torx Method to adjust your screen? If you have then you could have turned them a little to far and caused the connection between the phone and the sim card to become a little spotty.
If your not global take the sim out. its only needed if you go overseas. i pulled mine the 2nd day i had my phone and was getting the error. verizon will replace the whole phone if u take it in for sim card error.
