So sorry to hear it. Sometimes it's hard when they make it and you have a scrawny, weak chick who needs special care. Sometimes they do great so it makes it worth a try. It's always hard when you lose one. Hope the rest of your hatch went well.
That happens really commonly, even under hens at times. I swear some of the little buggers get claustrophobic and bang out too soon. If protected from other chicks and kept from tearing the yolk it usually is better in twelve hours, sometimes less. Any not better my 24 have an internal problem preventing absorption.
Usually the ones that take longest don't do well. But the ones who take12-18 hours are often perfectly fine in the end.