When I export captions and closed captions, why do my closed captions show up as black bars?

Hi all! I want to export the closed captions in each of our project so we have a written record of what they all say (we no longer have the scripts). When I export them, the closed captions show up as black bars. If you search the document for key words they will show up, so apparently the closed captioning text is hidden within the black bars. I have tried changing the color of the Word document, but that didn't help. Any other recommendations?