My babies were a bit nippy when they were younger. It happens sometimes
I worked with one for awhile that was so foul tempered we nicknamed him "grimmace" but even he came around.
Make sure that when he is "at home" he feels safe and secure. A nervous beardie is going to be more apt to bite. Make sure he has a spot where he can hide completely from anything he percieves to be threatening. You might even try covering part of the cage to give him an area of dark recluse.
If he is calm and content in his home, then just make sure to hold him frequently (as long as he does not appear too stressed out) hold him gently on one hand inside his enclosure so he doesn't feel so scared and so if he jumps you wont lose him. As he gets used to being handled you can slowly take him out of his enclosure. The world is a scary place to a little beardie!
Also, try hand feeding peices of lettuce or the occasional mealworm (if he is big enough, i forget how big you said he was, if you did) or waxworm.
Good luck! Keep posting if you need any help
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