Do you mean his viv is 12 inches HIGH? If so, that is way way too short. They do sleep all day, they are nocturnal. Mine sleep in the same spots every single day, so sometimes it looks as if they haven't moved. Can you share some pics so we can get an idea of what is going on? I bowl feed my tree frogs, I like it because I can monitor how much they're eating, the crickets are less likely to be running around my house, and my frogs will not accidentally eat something they shouldn't. If the bowl is at least 1.5 inches tall, they should not escape it. Make sure the crickets are no bigger than the space between his eyes. What are your temps?
How long have you had him? He should be in a quarantine enclosure until you're sure he's healthy. That would be a plain tank with 3 sides covered, damp unprinted paper towel as substrate that's changed every 1-2 days, a water dish with dechlorinated that is cleaned daily, and maybe a branch and a plant in there for places to hide.
Here is a care sheet - Frog Forum - Red-Eyed Leaf Frog/Red Eyed Tree Frog Care - Agalychnis callidryas