Hi,
If this is their first clutch, then it is common for them to make mistakes. The best thing to do is give them their privacy. If their aren’t sitting all day and all night, the eggs aren’t going to hatch, but this is good practice. If these birds are not at least 2 years old, then they are not old enough to be breeding. They will make mistakes and are likely to develop bad breeding habits that will ruin them for being good breeders. Breaking eggs and not sitting on the eggs are common bad habits that young bird develop. If they are under 2 then you need to remove the nest box and discard the eggs and let them try again when they are older. If they are 2 or older, then leave them alone and let them learn. You should be feeding them a nutritionally balanced diet like pellets – not a seed diet. Also offer leafy greens, veggies & some fruit. They also need an egg food – either a dry commercial egg food or cook an egg with the shell washed, crushed and cooked with the eggs. Nesting bird eat a lot, especially if the eggs hatch. The female needs the extra nutrients because of forming and laying eggs. When they are done with these eggs, remove the box and rest the pair for 6 months before letting them breed again. A normal clutch size is 4-6 eggs, but some will lay as many as 8. If you are seeing one egg daily, then you probably have 2 females. They can only lay an egg every other day.
Thank you for asking Lafeber,
Brenda