Unfortunately I don't think that these phones can be unlocked.
My understanding is that they cost less money than they should because you can't take them away from the network that you bought them on.
Apparently as the software/firmware is customised for TracFone, it will be incompatible with other networks because the airtime timer can't be disabled. It will continue to function and when it gets to zero the phone will no longer work.
A security feature is that there is no way to access the programming as the usb port can't communicate with the programming and there is no recognition of other sims in order to input an unlock code.
I wish I had better news for you but it looks as though you either learn to love your network or buy a new phone.