Is your radio registering or is it just not scanning properly? You said "NAS" scan was not working. That would typically indicate to someone that the radio is affiliating/registering.
If it's just not scanning as it was before, try rebooting the radio first. Hold the front 2 buttons, on each side of the arrow pad, along with the PTT button, and then turn ON the radio to reboot it. It will indicate the mission plans and keys have been erased. You will have to reload your mission plan(s).