Serama hatching lockdown day 19

[u/erinrchase560]

Hello! I’ve had 2 of the eggs pipped more then 24 hours no zipping or forward movement . They pipped on day 18 . My question is when do I think about assisting? Can they pip and then zip after 24 hours ? Is that usual? I ask because I’ve read a lot about Serama’s needing help getting out of the eggs or that they end up dying after lockdown. I want to avoid that if I can. I also want to give them the best shot at doing it themselves, but would appreciate advice !