What troubleshooting have you tried? Do you have an active 4G signal when you attempt to send the messages? Reseated the SIM card? Replaced the SIM card?
I'm most definitely NOT a VZW employee. If a post answered your question, please mark it as the answer.
FlexyP, I want to make sure that this issue is resolved. Please try powering your device off, removing the SIM Card and reinserting it into the device.
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