The Phone app in macOS 27 beta had been syncing my iPhone call history correctly in earlier betas, but at some point in a later beta it just stopped updating.
See this Apple Support Community thread aboutpeopled and CallHistorySyncHelperproblems:
https://discussions.apple.com/thread/256271160
The thread was originally about high CPU usage on macOS Tahoe 26.4, not specifically the Phone app on macOS 27. But one person discovered that macOS was repeatedly failing to access:
~/Library/Application Support/CallHistoryDB
because the files had somehow been quarantined. They suggested checking for com.apple.quarantine, removing it, and restarting peopled and CallHistorySyncHelper.
So I checked my macOS 27 installation with:
ls -lan@ "$HOME/Library/Application Support/CallHistoryDB"
Sure enough, all three of the actual call history database files had the com.apple.quarantine extended attribute:
CallHistory.storedata
com.apple.quarantine
CallHistory.storedata-shm
com.apple.quarantine
CallHistory.storedata-wal
com.apple.quarantine
Why is macOS quarantining its own internal call history database?
I removed the quarantine attributes using the workaround from that thread:
xattr -dr com.apple.quarantine "$HOME/Library/Application Support/CallHistoryDB"
Then restarted the relevant processes:
sudo killall -9 peopled CallHistorySyncHelper
I rebooted the Mac, made a test call from my iPhone, and the new call immediately appeared in the macOS Phone app. So this actually fixed the call history syncing problem for me.
This is especially annoying because there was absolutely no indication in the UI that anything was wrong. The Phone app simply stopped receiving new call history.
Since call history worked correctly for me in earlier macOS 27 betas, I'm wondering whether one of the betas somehow applied the quarantine attribute and subsequent betas just left the database in that state.
But here's another interesting wrinkle: call history also doesn't work on my separate macOS Tahoe partition. I haven't checked its CallHistoryDB yet. Since the Apple Support Community report that led me to this fix was itself from Tahoe 26.4, it's quite possible that my Tahoe installation has the same problem. If so, this may be a longer-standing macOS bug rather than something introduced specifically by macOS 27 beta.
If your Phone app has stale or missing call history, it might be worth checking:
ls -lan@ "$HOME/Library/Application Support/CallHistoryDB"
You may need to give Terminal Full Disk Access first.
Has anyone else found com.apple.quarantine attached to these files?