Incubating call duck eggs

[jtalking]

I am having problems with my call duck eggs not hatching. I keep my still air incubator around 55% humidity and 100 degree until 2 days before and then I transfer them to my hatching incubator that is 65-70% humidity and 100 degrees. I put my eggs in my incubator as my hen lays them, so just about everyday I am supposed to have at least one hatch. Haven't seemed to have any hatch out yet and can't figure out the problem. I recently hatched out some mixed chicken eggs so I know my incubator is capable of hatching them out. Any info will be greatly appreciated!