Wrong color displaying on certain pages
I'm working on a book layout and it's 48 pages long, with facing pages. This is a science text book, and some of the text is bright BLUE instead of black. On spreads 8-9, 40-41 and 44-45 the blue text is showing up as navy, and even when I change the color, it still appears as the navy blue instead of bright blue. It seems like there must be a setting specific to these spreads, and not the text (although the text color starts out as navy when I highlight it to check the color). It looks like the paragraph styles all match, and I've tried using the eyedropper tool. Does anyone have any suggestions on what else I could try, or where I could go to learn more about page settings?
Thank you!