After several desperate tests, I opened the document on my old 2009 iMac and macOS Sierra. The file kept closing on save, apparently the file had become corrupted at some point (I don't know if it was due to the Monterey update or saving to Google Drive).
I could export without problem to other formats but never make a new copy of the document.
I found a workaround that worked for me, I unlinked all the symbols in my document and saved a new copy to the desktop. This seems to have worked and I have been able to continue working on my document. I lost the symbol linking but at least not all the layer editing.
I hope it may help more people.