How long have you had him in there. I'm not sure of the reason but when I mobed mine to his cage he did the exact same thing after a while he was happy again.
oops
That's how I trained my bearded dragon onto pellets he ate superworms and meal worms (got him off those quick) I took a super and covered it half way with pellets and he ate them both.
I just took a pop bottle and cut the bottom of it out, the crickets I have a too small to jump out and most worms cant climb smooth plastic.
Good luck.
I named mine Tim because Tim Conway did the oldset man in the world shuffle and when I bought him he was doing the leaf and it reminded me of the oldest man in the world.:)
That gives 120 gallons worth of room. My little guy is pretty small will he get scared in a tank that big. Also how long till he reachs full size. Any idea on age?