I had the same problem last night. Followed the instructions to disconnect the power from the box and reconnect and even rebooted the router but the problem wasn't fixed. Called Verizon this morning and there was about a 30 minute wait for customer service. Left my name and number for a call back. They called me 30 minutes later and were able to update the firmware on the box from their end and problem solved.
Once they called it only took about 5 minutes to get everything working again and another 5 minutes to make sure the box was functioning ok. Hope this helps.