I see the problem. You're invading HIS home. What would you do if a giant hand came through your bedroom window? Your instinct is to protect yourself by any means.

I'd suggest teaching him that you = food. Does he get playtime outside of his cage? Say, letting him roam around on an enclosed desk area around his cage - have his cage door open and let him come out when he wants to. Let him get used to you. Don't try to teach him that you're good by sticking your hand in the cage with food.

How long have you had him? He may just be scared because he doesn't know the scents and where he is. Again, think about it as if YOU were in his place. You'd be scared too.

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