So sorry. See if the chick had any deformities. Sometimes it happens and you just never know why. In the future if you are around during hatch and notice that it started to zip, like yours did, but no progress after an hour or so, pull it out and see what’s going on. Once they are zipping all the blood (veins) and yolk are absorbed so don’t be afraid to offer help at that point.Thanks, photos in my post above. Ideas about what went wrong?