Files automatically locked after latest update (CALC)

After updating to the latest version about a week ago, we have been experiencing problems with our computers.

Files are automatically locked after they have been updated.

Example: I open an old file in CALC, do some editing, save, and then close file. Now the file is locked, and there is a hidden “.~lock” file in the same folder.

We are using ESET NOD anti virus program. Windows 11 (version 25H2) and updated in WINDOWS UPDATE.

Our problem started about week ago, when all computers were updated together with LIBREOFFICE.
Why?

We haven’t changed any settings in LIBREOFFICE, nor in CALC.

The file is NOT inside ONEDRIVE or DROPBOX or any other cloud (so it’s not the problem with issues with Windows update KB5074109 error.)

but still shared ?