I’m guessing by “2 windows”, you mean 2 panes of glass.
Most replacement windows are designed around an insulated sash. The sash is the pat of the window you slide up and down. There are usually 2 panels of glass from ¼ to ¾ inch apart. The space between them is sealed from the outside, and either contains one of several inert gases that aid in insulation, or may simply be under a vacuum, with most of the air sucked out. Anyway, this space is completely sealed so that whatever is between the glass panels remains there.
If that is where you are finding moisture, then somehow whatever seals the 2 panes of glass has failed. The problem is that the moisture is between the glass panels, so you can’t get at it to wipe it away. Furthermore, most of these windows have a coating on the inside surfaces of the 2 glass panels, which will discolor from the moisture. Eventually, it can turn the window opaque, like frosted glass.
Is that what you have? Is it still under warrantee? Please let us know.