Ecm won't unlock after tune

[05chevy]

I just tuned a 02 lb7 and let my efi live controller generate the lock key for this truck. Go back to late after I made some changes to flash again. Now I get a error and it will not unlock the ecm. Or isn't recognized be the efi live controller. Any help with this issue or what did I do wrong. Truck runs and drives. Just won't let me access the pcm. Thank you

[05chevy]

Any help?

[killerbee]

We can evaluate here on the bench if you like. We also can service a replacement if it is locked.