Reset the Jetpack (Page 79 in the User Guide). Remove and reinstall the SIM Card located beneath the battery (page 11 & 12). Be careful not to damage it, the retain clip or frame in any way.
If this does not resolve the problem you probably need to call Verizon Wireless Customer Service (800) 922-0204 for a replacement SIM Card or Jetpack (if under warranty).
I understand how important it is to have your device up and running. Removing and re-inserting is definitely one of the steps to troubleshoot the device. Is there any damage to it? You can also get a SIM card at no cost at one of our corporate stores.
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I kept having the same problem. Eventually, I ended up taking the sim out and cleaning off some extra plastic on the insert side, which was probably leftover from the mold. Works fine now.
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