Budgie Breeding

Hi everyone,

I have a pair of budgies, definitely male and female, definitely over 1 year old that are bonded. They sleep together, feed each other and groom each other. I have had a nest box in with them for about six months now. Veges and fruits available, seed, pellets, cuttlefish bone and multiple perches. In the box I have unscented pine wood shavings and even put fake eggs in there. I have only seen her go in once when I first put it in but only for a minute or so. I have not seen them mate yet. I have other budgies in cages around them. I think they are in Breeding condition. I have researched for hours over the last few weeks and have done everything I can. They are both jumping around and seem happy. The male comes and sings. So why won't they breed?

Thanks,

Amy