On day 25 please help

[Ercwyne]

I have 31 eggs in the incubator and none of them have hatched. Currently on day 25. This is my first time incubating.
I checked the temp of the incubator early in the process to check that it was accurate.
I increased the humidity to 65-70% for lockdown.
I was waiting, waiting, nothing so I decided to candle a couple eggs quickly last night and theres visible air sacs. One of the eggs started wobbling while i was trying to candle so theyre still alive.
I'm wondering if the forced air is no good and making them cool down? What should I do? Im so anxious I really want this hatch!
Theyre pekin and pekin silkie cross.

 

[nuthatched]

Have you calibrated the temperature?

 

[Ercwyne]

Have you calibrated the temperature?

Yes its been a steady 37.5 degrees C

 

[McChooky]

Where did you get your eggs?

 

[Ercwyne]

Where did you get your eggs?

From my own chickens. Father is a pekin. Mothers are 1 pekin and 2 silkies. We no longer own the rooster because we had to get rid of him due to council laws, so this is the only chance ive got with my own chickens.