Face styles not working

I am new to sketch up. I am still learning how to use the basic tools. I am having an issue with the face styles. they are not working. my polygons are perfectly closed, but they do not shade. I have tried changing the style, but the faces do not shade. Can you help? thank you

How did you make the polygons?
If the edges are not coplanar, there will be no face formed…
Easyest solution is to draw a large rectangle and draw your polygons on that.

Attach your model so we can see what you have and advise from there.