Nigelplizga, allow me to be the very first to welcome you to the Verizon Wireless family. When porting a number from another carrier it may take up to 72 hours for all services to be transferred. Are you able to text and receive messages from other numbers? You mentioned receiving a recording when calling Verizon, are you able to place other calls from your phone? Have you powered the phone off and on with Wi-Fi off and cellular data on?
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I tried a network reset on my iPhone X - nothing. I force restarted it in multiple ways. Finally I powered down normal and turned back on w/ wifi (not connected) and cell enabled. Short-code texts are working finally! Hope it works for you.