Hi Tony - sounds like Sway thinks you have 160 paragraphs for some reason. It's not supposed to count empty paragraphs, but if you have empty paragraphs that contain spaces, those might be counted. Any chance that could make a difference?
Could there be some extra long captions on images that you might be able to shorten? I think those are counted as well.
If neither of those things helps, then if you're happy for me to take a look at your sway, please post a link to it and I could make a suggestion.