Bug: "Document already saved"!

There's a very annoying bug on Zoho Docs! I importing a Doc file from Google Docs, and after I made the first changes, I could save the file. But when I continue to make changes after the first save, I can't save the changes anymore! Any subsequent attempt to save the file would result in a message "Document already saved". This is ridiculous! I have made siginificant changes, not minor ones, and yet they can't be saved at all. When is Zoho going to fix this bug?