Does he have toys in his cage? I try to make sure all my birds have enjoyable things in their cage, so they don't mind the time they spend inside. I always have a treat, a nut or a toy ready, so they almost look forward to it.
My Military put up a fuss last night, when I was trying to put him in. He yelled, and fought a bit. I took him out, pet him for a few seconds, and told him it was night night time. Then I put my hand gently on his back, and he went in, no problem. I don't know why he didn't want to go in, but by giving him the extra consideration of consoling him for a few minutes, I let him know that his feelings matter. Imagine if you had very little choice of what happens to you. When and what you eat. When and how much time you spend in a cage. How many hours of light and darkness there are.....basically everything in their world depends on us. So to respect their feelings, and give them choices when we can, or the ability to express their feelings makes a big difference in their lives.