My pages document won't connect to iCloud

I am using Pages 14. My collaborator is using iCloud via Safari on an older MacBook Air. Today, I cannot get the document to sync in Pages, it says it isn't connected but I can collaborate in real time through iCloud. There are no services down. This is a legal filing and I have no time to waste. What to do I do to get Pages to connect to iCloud properly? Yes, other internet applications work fine.