Apple has finally fixed a persistent CloudKit bug that was causing iCloud sync issues for many third-party developers and their users.
How to Fix iCloud Syncing Issue on Your iPhone (EASY!)
In November 2021, developers began reporting CloudKit bugs that caused previously working sync features to stop working. The persistent issues even led some developers to drop sync features altogether. Now, Apple has confirmed that they are investigating the bug and said that their engineers have implemented a fix.
The bug often resulted in users receiving a “Request failed” 503 error or “Service Unavailable” error, even if the developer had not changed the underlying app code. As a result, many users were unable to properly sync their data between devices.
Unable to reproduce the bug to resolve the issue, developers contacted Apple for assistance, but were often directed to Apple's Feedback Assistant. Apple confirmed that they were investigating these reports, but did not comment on why developers were being told to contact Feedback Assistant instead of Support.
