egg hatching upside down what to do???

[Booboochicken7]

I have two eggs that are currently hatching upside down . I had one earlier do the same and didn't make the zip before dying. I do not want the others to die!! Do I need to assist or should I just let it happen naturally? Oh a little off subject but I also had a chick hatch with a small yolk sac still attached . He seems to be doing ok drinking eating already and walking around the brooder. Should I just leave it alone and let the yolk hopefully dry up or should it be carefully removed? He is now 27 hours old. Thanks

Incubator temp 99.6-100
Humidity says 55% but I believe it may be wrong because all water wells are full and there is a bowl of water in the incu as well and it never changes. A shame being it is a new incubator.
Both vent plugs are pulled
LCD reads perfect hatch set

 

[chicklover 1998]

if they are upside down you can turn them the other way but if they have already externally pipped then you could help it, as for the one with the yolk just keep an eye on it don't do anything to it, it will either dry out and fall off or it will absorb it.