Keynote "The document could not be autosaved."

Mojave 10.14.6

I have a large keynote file. All of a sudden it is giving me an error that says.

I cannot duplicate the document.

I tried creating a new document and pasting the contents into that. I got the same error with the new file.

When I quit, I am forced to "Discard" all changes.

I have tried duplicating the file in the Finder as well.

I Tried some other tips like:

File>Recent>Clear Menu

I changed the File permissions for ALL to "Read & Edit"

No luck.

This is a big presentation and I need to move forward with it.

Please help!!