If document versions conflict in iCloud Drive on Mac
Conflicts can occur when you use more than one device that’s not connected to the internet to edit the same document stored in iCloud Drive. As the devices go online, they save your changes in iCloud Drive. When you view the document, a message appears asking you to select the document versions you want to keep.
In the conflict resolution dialog, select each version of the document you want to keep, then click Keep.
To preview a version, double-click its icon.
If you keep multiple versions, a different number is added to each version’s name except the first one. For example, two versions of “Seven Wonders” are named “Seven Wonders” and “Seven Wonders 2.”
Versions you don’t select are deleted from iCloud Drive on all your computers, iOS devices, and iPadOS devices set up for iCloud.
If you kept multiple versions but want only one, open the versions and merge the changes into one document.