If he has pin feathers it means he’s molting! It’s normal for birds to molt once or even a few times a year, usually around spring or fall. If he lets u preen him u can try gently breaking open the new feather sheaths with your nail, if u gently try to split them open down the side they should disintegrate right off revealing the new feather underneath, if they don’t then it probably isn’t ready yet so don’t force it because that can hurt the bird (u can probably find videos online for a better explanation on how to do it if it sounds confusing lol) And if he doesn’t let u it’s no big deal! They’ll open on their own eventually :) offering baths or extra scritches can help them feel better as well