you shouldnt bother him while he’s sleeping. The only time this is a concern is if he is doing it every single night, but baby chams are known to do weird things like screen climb upside down and i’m sure he’s just sleeping on the screen cause he’s getting used to his new enclosure, my little guy has fallen asleep on his screen a few times. The only thing i would recommend is maybe to add more sticks if there isn’t enough places for your cham to hide, but if you could provide pictures that’d be awesome