When a pair that has produced before stops producing, I always recommend a Vet check to begin with, just to make sure both birds are 100% healthy.
One of the rules of breeding is when you do have a successful pair, do not change a thing except to make them rest in between clutches. In fact changing the cage, environment and routine is something that will make most pairs stop breeding. Some pairs will try to have one clutch after the other, and with that kind of pair, the nest box has to be blocked off or removed, and the pair forced to rest from laying eggs for 6 months after each clutch.
Of course sometimes changes are necessary because our lives change. You made at least 2 major changes – you changed their nest box and you changed where their cage is. And also the cage if this is a new cage. It sounds to me like they do not feel safe in the new nest box. I would guess that they either didn’t sit on the eggs last year at all, or didn’t sit at night. Now the female doesn’t want to lay her eggs in that box at all. She doesn’t view it as a safe place to incubate eggs or raise chicks. She may feel too exposed of the cage is outside, but not in an outdoor enclosure. Parrots are prey animals, so anything moving around outside is a potential predator in her eyes. And there are plenty of real predators – cats, dogs, rats, raccoons and other wild animals. If there are any nearby houses, lights from those houses or even from your house may be bothering them. If there is a road nearby, headlights can be alarming, or just road noises. You need to try to determine what might be scaring them, and then do what it takes to remove that danger. Many outdoor parrots have a second enclosure around their cage – a screened building or something similar. This can provide some security from predators and from escape, as well as making the pair feel safer. This could still be something medical, but I think chances are they haven’t accepted their new environment and aren’t willing to risk raising chicks there.
Thank you for Asking Lafeber,