zub

I have 8 budgies in a 2 metre tall 1metre length and 1 metre width. I have 4 males and 4 females and 3 breeding boxes high up in the cage (i only have 3 because 2 of the budgies are 2 months old) 2 of my pairs were in healthy condition going into their breeding boxes 2 weeks after buying them. But i had made the mistake of thinking they needed nesting material so i put shredded newspaper in and they never went back in . I took the news paper out a week and half ago and have never seen them go in their again. They are outside my veranda in shade get the right amount of lighting a day and no known predators near bye. They are also out of the wind. Please help me