2 year old bearded dragon not eating as much?

I've been having this problem for a few months now, and I have tried almost everything.

My lizard, Bentley is ~15-16 inches long, and when I weigh him, his weight always comes up around 426 grams. The problem is, however, he looks skinny. His body appears smaller than other bearded dragons, who are more filled out. He is not. He also has not been eating as much. This wasn't a problem until a few months ago, so it was a very sudden change. He stopped eating foods he would usually like. He rarely eats anything at all. I don't think heat would have anything to do with this; His cage is constantly between 100-110 degrees F, and he has a UV light. I love my beardie, and I want the best for him. I tried fixing this on my own, but after many failed attempts, I'm asking for help.

Any advice on what I should do? Is there anything I should look out for? Am I just being paranoid..? Any help is appreciated..!!

Thank you!! (Pictures added so you can see for yourself! ^^)

426g is a bit small for an adult. Which UVB light are you using? How far is it from his basking area? 100-110 is a good surface temp range for the basking area but he also needs areas that are cooler. 75-80 or so during the day. I'm not able to see your photos. Can you try uploading them here https://www.beardeddragon.org/useruploads/ and post them to your thread using the XIMG button?