It’s entirely possible that the chicks didn’t survive and the parents just built on top of them, or the parents may have built on top of them and smothered them. I really think you would be hearing sounds if the chicks were alive. I would take all the nesting material away except what is in the nest. Once eggs are laid, they do not need more nesting material, and some pairs in captivity seem to get obsessed with building the nest but do nothing to care for any chicks that hatch. Some lay eggs, build on top of those, lay more, build, lay until they can’t get in the nest. So always remove extra nesting material once the initial nest is ready. It may be that nesting material is harder to find in the wild so they don’t fly long distances to find more once they have eggs, but in captivity, it is right there for them so they keep building as long as they have some. Just to confirm you have the right type of nest, they prefer the hut type with a small opening, not the fully open nests that are shaped like a small bowl.
Once you remove the extra nesting material, watch for any signs that they are feeding chicks. Are you providing egg food for them? This can be a dry commercial egg food or you can cook an egg with the shell washed, crushed and cooked with the egg. You only provide egg food when they are set up for breeding with a nest. Are you feeding finch pellets or granules, or just seeds? Seeds aren’t going to provide the nutrition the need, so they really need a pellet or granule. You should also offer dark leafy greens and chopped veggies. Most finches also enjoy broccoli florets. The greens can be given in large leaves on the cage floor or attached to the side of the cage, and you can clip a broccoli floret to the side of the cage for them to eat.
If you determine there are no chicks, then go ahead and remove the nest and rest the pair for 4-6 months. With finches, you can allow up to three clutches per year, with a 4-6 month rest in between. If they do successfully raise chicks, always remove the chicks as soon as they are weaned or you will not be able to tell them apart from the adults within a few months. And separate the chicks by sex so they do not try to breed with each other.
Thank you for asking Lafeber,