Really not sure. The only time I had it happen the chick didn't make it, but it was out with a broody.That looks like the yolk sack was not absorbed properly prior to hatching in the first photo. The second photo looks like it may have ruptured.
@Debbie292d
If it ruptured the chick is at much higher risk of infections. I'd isolate so other chicks don't pick at it.
Midway in this article discusses chicks with unabsorbed yolks for future reference:
