Bricked? Don't know what to look for!

[vestaviajag]

So I destroyed my 6700 by accident. Finally got a new one in the mail off eBay. They are both Alltel, I activated, made a few calls with it, but then it started acting up last night. I haven't a clue why. Heres the issues...

Don't receive any calls from other people.
Can't send SMS (Sent a few, like 3, it usually doesn't work)
Always get a Ntwk.NoRdy error, "Send when digital service is avail.?"

Other than that, the phone looks and works (for the most part) just like my old one. I've tried searching for any of this, and I couldn't find anything that helped. I can make calls no problem, but when I went to bed last night, this morning, I had 3 unread texts, and a voicemail. No missed calls though.

What can I do? Please help! Thanks