Frilled dragon weird behavior

[Will0W783]

I have a female frilled dragon lizard of unknown age. I got her from a guy who got her from a guy he knew who got her from a pet store he worked at. So, no idea how old she is. But she is shedding well and seems to be in good health. She had a full vet check right after I got her. My question is- can reptiles get anything like a form of narcolepsy? I know it sounds bizarre, but she falls asleep ALL THE TIME. She will crawl up a branch and fall asleep in mid-step. She also falls asleep with mice hoppers in her mouth. She will zealously chase it, kill it, crunch, crunch..zzzzzzzzzzzzzzzzzzzz.
She'll just pass out with the thing hanging out of her mouth! If I wake her up, she will look around like, "huh? Wha..oh yeah, I was eating" and start munching again, then she's out like a light again after a few chomps. What the heck?? I'm at a loss here.. She has plenty of heat, the temps are in the 80s during the day with a basking spot near 90. She has a UVB bulb. She always has water and branches to climb on and she is in a 55-gallon tank so she has plenty of room. Anyone have any idea what could be going on?