Beforehand, he always used to poop him his own box. However now, I am starting to see more and more poops around the room, not at the box. Is there a reason for this?
Litter habits will likely improve after he is neutered and has a few weeks for hormones to fade. Litter habits can go out the door when those teenage hormones set in. But even then, territorial poop marking can occur for a variety of reasons like being in a new room, changes to a rabbits environment, new people or pets in the house. And some rabbits are just better at keeping the poop in the litter box than others.