I did a system updated this morning and since then I can't text & keep getting denial, "iPhone is not Activated - Contact your carrier at (800) 922-0204 from another phone if this problem continues to occur" / Someone Please Help!!!! I just got my phone 2 days ago & it worked perfectly fine....
You can do a few things if you don't call Verizon.
First hold the on/off button and the large home button together until you see the apple logo. Release both buttons. Wait until the device resets.
You can also turn the phone off and carefully remove the Sim card with the Sim removal tool that came with the device.
Then wait a few minutes and carefully replace it back into the phone. Turn it on and see if it functions as before.
You can also go to a Verizon wireless corporate store and have them activate or troubleshoot the device. If you need a new Sim card they have them right there.
You can visit the Apple site http://www.apple.com/support
And search for activation solutions.
Or just call Verizon as the phone said from another phone.