Passwords (iCloud Keychain) synchronization

There are two devices linked to the same iCloud account: an iPhone and a Mac. The “Passwords” (iCloud Keychain) app was set to sync with iCloud on both the iPhone and the Mac.

At some point, I disabled iCloud sync for the Passwords app on the Mac and manually deleted all saved passwords on the Mac. On the iPhone, iCloud sync for the Passwords app remained enabled, and all logins and passwords (around 200 accounts) were still present.

Later, I re-enabled iCloud sync for the Passwords app on the Mac. Instead of passwords being downloaded from iCloud to the Mac, the empty state of the Mac was pushed to iCloud, and as a result, all saved logins and passwords were deleted from both iCloud and the iPhone.

How can I recover the lost (deleted) logins and passwords?

What I tried:

I restored an old iPhone as a new device using an iCloud backup dated July 7, 2025. However, in the “Passwords” app, the data was synced from iCloud in its current (empty) state, not from the backup itself.

[Re-Titled by Moderator]

Original Title: Passwords (iCloud Keychain) synchronization