Quail egg emergency on day 17

[Nabiki]

I will agree with the rest that the chick that didn't make it wasn't due to you opening the incubator. I also agree that your humidity was probably too high.

Your incubator may still work for you, but I do recommend putting in a calibrated thermometer or three. Even good incubators often lie about temperature and humidity.

 

[Smeksmek]

The incubator is a cheaper one I got from eBay. It holds the temperature well at 37,8°C. Don't know whats that in Fahrenheit. However, it doesn't show the humidity level, so we added a hygrometer. That was calibrated.
From day one to 14 I kept the humidity between 40-50%, but I had some trouble keeping it steady. It never dropped under 40% but would occasionally go up to 80%. The incubator only has one hole in the lid for air, so I opened the lid a tiny bit to get some humidity out and oxygen in when I noticed the percentage going up.
I'm not sure why it was fluctuating that much, but again, cheap incubator
I've read before that the humidity should be raised to up to 90 % while in lockdown, but here in the forum I've seen so many different opinions. In my case has been between 70-90% since day 15, so two days ago.

Humidity 75-80 average at lockdown.i do day 15 I had to put. A govee temp/hygrometer in with mine because cheap ebay incubator. Sorry their temp gages aren't always accurate. 35-50%humidity before lockdown.youre trying to keep them a little dryer so the inside membrane doesn't stretch so much that when they pop through it, they have enough oxygen to complete their escape from the shell. You can read up on dry hatching also but ive never done it. I hope this helps. Just put mine in lockdown this morning uts like being a mom. Trying to regulate after candling(I do it when I lockdown) and I put a shelf liner in the bottom

 

[Smeksmek]

Humidity 75-80 average at lockdown.i do day 15 I had to put. A govee temp/hygrometer in with mine because cheap ebay incubator. Sorry their temp gages aren't always accurate. 35-50%humidity before lockdown.youre trying to keep them a little dryer so the inside membrane doesn't stretch so much that when they pop through it, they have enough oxygen to complete their escape from the shell. You can read up on dry hatching also but ive never done it. I hope this helps. Just put mine in lockdown this morning uts like being a mom. Trying to regulate after candling(I do it when I lockdown) and I put a shelf liner in the bottom

 

[Nabiki]

Your humidity is too high. See if you can get it down to 60% or so.