Keynote Collaborate not working

I have been working on Keynote and using the Collaborate feature extensively to put together presentations as a team together - and it's the key feature that helps us work fast. However this has stopped working recently.

Here are my issues.

1. When i make a new presentation and hit the Collaborate button, and choose to share by email - i get the error "Sorry, your invitation couldn't be sent". Instead i have to select to copy the link and share that instead.

2. Once Collaboration has begun (this could be me starting it, or a keynote shared by someone else) the Collaborate icon never turns green. Live editing cannot be seen or not functional. Instead once in a while when the icloud folder gets updated - then the whole presentation shows the changes someone else has done. When i try to click on the Collaborate button it sends me on a loop saying that it needs to be on iCloud (even though it is there already).

This image is from a file where several people are already collaborating. Note it's not green like it should be:

this is what happens when i click on the Collaborate button. It just renames the file by adding a "2" at the end of the file name within iCloud drive. Clicking on the Collaborate button brings this error again and adding another "2". in the end you have a filename like "AnnoyingKeynoteFileName 2 2 2 2 2 2.key"

This is driving me really nuts right now. Would like to know what's causing this and how i can fix it. For now i'm just using the web version which shows live edits - but doesnt support all the fonts.