Motorola V170 Problem

I've a Motorola Tracfone V170, and we've had it for quite a while, I know that if a certain date passes that you've not gotten any minutes then it will be deactivated, but the time passed and we still had 80 units on the cell phone, yet it still continues to say "No Service" and "Unregistered SIM", but it says we have 80 minutes/units on it, so what's going on?

Do I >REALLY< have to buy another airtime card to reactivate it, or is there some way I can get it turned back on without having to pay like $40?

Please help me.. ;__;