Just a shot in the dark: Maybe power down, remove SIM card, wait a bit (remove battery too) and reinsert both, power on. Could be a glitch with the SIM and a new one is free at Verizon corporate retail stores and via customer service.
You might also try to clear the cache and delete data for the messaging app in the App Manager in Settings. Might also delete all messages in the app. SMS Backup and Restore in the Google Play Store is an idea if you want to keep any messages.
I might perform those steps in that order.