Adding part to the sides of an object don't appear when sliced

SketchUp
#1

I have built a small window for a project for my son. On either side there are two “teeth” on either side and when I slice, the two parts do not slice. Is there something that I can do to fix it?
3WindowHolder.skp (114.1 KB)

#2

There are internal faces under those wedges. Delete them.

Screenshot - 1_18_2023 , 2_28_32 PM
Screenshot - 1_18_2023 , 2_28_32 PM761×527 19.8 KB

There are internal faces under the bevels, too. They need to be removed.

#3

Compare this one to yours.
3WindowHolder solid.skp (114.1 KB)

#4

Thank you. I completely forgot about that