Hi there, welcome to BYC!
Sorry you are having hatch trouble.
Please enlighten me... what incubator are you using, is it forced or still air? Do you have all the plugs out? Are you adding water into it? What is your humidity inside the bator during incubation and then at hatch? Is inside the incubator dripping with condensation? Are you using a calibrated thermometer or hygrometer? What breed or color eggs are you hatching? Are they from your own breeding stock or someone else's? Hatching taking place on day 21?
Sometimes they can look wet when it is dried on egg gunk gluing their feathers down.
When you remove chicks to dry, what are you doing with them? How long before they pass? Do they ever make it all the way up onto their feet? Or start pecking at things?
Have you ever heard of a "dry hatch" before? Here is an article that describes the idea... Please note that it may or may not mean adding some water, depending on your location and how dry your ambient air is to reach the desired humidity inside the bator...
https://www.backyardchickens.com/ar...h-eggs-using-the-dry-incubation-method.47694/
Adding your general location to your profile can help peeps make the best suggestions possible at a glance.
Sorry so many questions.

Just trying to gather clues that might be helpful to the big picture.
There are many things that can be done to lower humidity depending on what's currently taking place, So I will make more suggestions once I have more information available. Hopefully more hatch-a-holics will chime in as well.
