I'm very familiar with phone authentication. An authentication problem can generally be fixed by powering your phone off and on. If that doesn't work, and it's a 3G device, you can dial *228 Send and choose option 1. If that fails, a quick call to tech support will resolve your issue. The direct number is 866-892-7957. You can also send me a DM through the forum, and I'll call you as soon as I can.
Follow us on Twitter @VZWSupport