Pages missing part of a document
I am new to using Pages on macOS (though I've used it a lot in iOS). I've got a long document (500+ pages) and I'm experiencing an issue where part of some paragraphs are disappearing between the page breaks, making it look like something was deleted. The text is still there; I can select the area before and after the page break and when I copy and paste, the missing text is right where it should be, but I can't find a way to make the document show these missing lines between the page breaks. I was able to copy and paste the entire document to a new document which seems to have fixed the problem for now, but I'm concerned that it will happen again. Anyone know of a more permanent fix for this?
I'm using the 2020 MacBook Air with the i3 processor, and both the MacBook and Pages are fully up to date.
MacBook Air 13", macOS 10.15