How can deleted contacts on an iPhone be re-synchronized via CardDAV?

If contacts were deleted on an iPhone but still exist in the data source via sync.blue®, a re-synchronization may be necessary to retrieve them. Since iOS/CardDAV does not automatically detect that a re-synchronization is necessary, it must be initiated manually.

✅ Method A (Recommended): Temporarily disable and re-enable the CardDAV account

This method is the quickest and easiest to perform.

• Open the Settings app on your iPhone.
• Navigate to Contacts Accounts.
• Select the existing sync.blue® CardDAV account.
• Disable the switch for Contacts and wait about 30 seconds.
• Then, re-enable the switch for Contacts.
• The deleted contacts that still exist in the source will now be reloaded.

🔁 Method B: Create a temporary contact on the iPhone

If Method A doesn't work, this little trick often helps:

• Open the Contacts app on your iPhone.
• Create a new, arbitrary contact – e.g., "Test Contact".
• Wait approximately 1–2 minutes for the sync to complete.
• Delete the temporary contact again.
• The deleted contacts will be reloaded.

⏳ Method C: Wait for changes in the data source

If you don't want to make any changes on your iPhone, you can also make a change on the source side.

• Wait until a new contact is created or an existing contact is modified in the source.
• sync.blue® will detect this change and automatically trigger a complete update of the CardDAV destination.
• The previously deleted contacts will then reappear on the iPhone.

💡 Recommendation

Method A (temporarily disabling the CardDAV account) is the fastest and offers direct control. Use the alternatives only if method A does not produce the desired result.

Our support team will be happy to assist you with any problems.