This post has been moved as it is not really a discussion about Archicad so does not really belong in "Archicad+".
I would say it is a problem with the cloud sync.
My company does not use a cloud sync but it does have a live sync with other servers in the company.
I have noticed if I save a file directly to a server and then hit save again straight away, it wants to do a save as.
If I leave for just 10 or 20 seconds I can save again with no problem.
I think as Minh has suggested, during the sync process, the file becomes locked.
As soon as the syncing is finished, it should be released again.
Barry.
One of the forum moderators.
Versions 6.5 to 27
i7-10700 @ 2.9Ghz, 32GB ram, GeForce RTX 2060 (6GB), Windows 10
Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11