Maybe a wrong prl? did you try to go to
www.corolada.com/prl , download the latest PRL from alltel save on your Sd card and load it with EPST?
Try dialing *611 and see if you get an Alltel recording. if you're getting sprint or verizon, you do have the wrong PRL. If you're getting Alltel and still doesn't work, looks like it's an ESN related issue. they might have input the wrong ESN into their system