Invalid Character while Exporting Contents

I went to export the contents of my blog, as I want to transfer some posts to a new blog. When I went to open the exported Microsoft word content, a box popped up with the message “an invalid character was found in text content. Location: Line 15597, Column 88. No idea what that means or how I’m correctly supposed to download certain blog posts/pages.
WordPress 5.4.2 running Olsen theme.