If he was a trouble eater to begin with why didn't you take him back to the place you bought him? I would never buy an animal that starts to have trouble early on.

Since it sounds like he got over the behavior and has been actively been feeding for a year and stopped now all of a sudden. I would look for a couple of things.

I would check his temps to make sure they are on point. Although I really haven't heard of a bp killing an animal and not consume it. The only time I have seen this is when they have an RI infection, because they might want to eat but the RI infection makes it painful for them to eat. They will randomly, but its not regular and sometimes will stop all together.
You can check this by seeing if theres any weezing, discharge, and if you open his mouth there shouldn't be any buildup of bubbles. If you got any of that, you must take it to a vet to get it looked at.
I made a mistake when I started was I got a bp and it was sick. Ever since that, I don't mess around.

If everything checks out okay, try the paper bag trick and see if he eats properly than. If he eats there, I would just do what works. You got a bp that likes his privacy than lol.