CloudKit not updating schema and not syncing after schema change

Hi, I'm developing an app for iOS and MacOS with SwiftData and CloudKit syncing. I had sync working very well with a set of models. This schema was also pushed to CloudKit production.

Last week I added several models, and several relationship properties linking my existing models to newly added models. The schema updated just fine and everything worked.

Then things went sideways: earlier this week I decided I wanted to rename a property on one of my new models. So I renamed the property, removed the application support folder for my local debug app (on Mac OS), removed the app from the iOS Simulator (to clear its local database), and finally reset my CloudKit container to its Production schema. Basically, I tried to go back to the same state I had as when I first added the new models.

However, this time things don't go so smoothly, even after starting the app several times, rebooting my machine, turning iCloud on and off in Xcode and MacOS and iOS. When I look in CloudKit console, I see only my old models there: none of the new ones are added.

I'd love some pointers on how I can best debug this issue, as I feel completely stuck.

On MacOS

I have very little

to go on. Since the logs are a bit lengthy I've added them as an attachment. I get a few warnings, but it is unclear what they are warning me about.

One thing that does stand out is that I am running the CloudKit in Development mode here. However, the logs do state accountPartition=Prod . And when I query CKContainer.default() for the container environment, the response is sandbox, which matches Development!

On iOS

The logs show a few errors, but I cannot make sense of them.

error: CoreData+CloudKit: -[NSCloudKitMirroringDelegate _performSetupRequest:]_block_invoke(1240): <NSCloudKitMirroringDelegate: 0x600003d09860>: Failed to set up CloudKit integration for store: <NSSQLCore: 0x103325c90> (URL: file:///Users/bastiaan/Library/Developer/CoreSimulator/Devices/BF847CE5-A3E2-4B4C-8CD5-616B75B29AFE/data/Containers/Data/Application/0A916F67-B9B2-457B-8FA7-8C42819EA9AA/Library/Application%20Support/default.store)
<CKError 0x600000c433f0: "Partial Failure" (2/1011); "Failed to modify some record zones"; partial errors: {
	com.apple.coredata.cloudkit.zone:__defaultOwner__ = <CKError 0x600000c956b0: "Internal Error" (1/5005); "Couldn't create new PCS blob for zone <CKRecordZoneID: 0x600000c475d0; zoneName=com.apple.coredata.cloudkit.zone, ownerName=__defaultOwner__>">
}>
error: CoreData+CloudKit: -[NSCloudKitMirroringDelegate recoverFromError:](2310): <NSCloudKitMirroringDelegate: 0x600003d09860> - Attempting recovery from error: <CKError 0x600000c433f0: "Partial Failure" (2/1011); "Failed to modify some record zones"; partial errors: {
	com.apple.coredata.cloudkit.zone:__defaultOwner__ = <CKError 0x600000c956b0: "Internal Error" (1/5005); "Couldn't create new PCS blob for zone <CKRecordZoneID: 0x600000c475d0; zoneName=com.apple.coredata.cloudkit.zone, ownerName=__defaultOwner__>">
}>
error: CoreData+CloudKit: -[NSCloudKitMirroringDelegate _recoverFromPartialError:forStore:inMonitor:]_block_invoke(2773): <NSCloudKitMirroringDelegate: 0x600003d09860>: Found unknown error as part of a partial failure: <CKError 0x600000c956b0: "Internal Error" (1/5005); "Couldn't create new PCS blob for zone <CKRecordZoneID: 0x600000c475d0; zoneName=com.apple.coredata.cloudkit.zone, ownerName=__defaultOwner__>">
error: CoreData+CloudKit: -[NSCloudKitMirroringDelegate _recoverFromPartialError:forStore:inMonitor:](2820): <NSCloudKitMirroringDelegate: 0x600003d09860>: Error recovery failed because the following fatal errors were found: {
    "<CKRecordZoneID: 0x600000c8fd50; zoneName=com.apple.coredata.cloudkit.zone, ownerName=__defaultOwner__>" = "<CKError 0x600000c956b0: \"Internal Error\" (1/5005); \"Couldn't create new PCS blob for zone <CKRecordZoneID: 0x600000c475d0; zoneName=com.apple.coredata.cloudkit.zone, ownerName=__defaultOwner__>\">";
}

And in CloudKit logs I see:

06/11/2024, 9:09:59 UTC 738513AC-9326-42DE-B4E2-DA51F6462943 iOS;18.1 ZoneFetch EphemeralGroup

{
"time":"06/11/2024, 9:09:59 UTC"
"database":"PRIVATE"
"zone":"com.apple.coredata.cloudkit.zone"
"userId":"_0d9445f850459ec351330ca0fde4134f"
"operationId":"611BA98C9B10D3F2"
"operationGroupName":"EphemeralGroup"
"operationType":"ZoneFetch"
"platform":"iPhone"
"clientOS":"iOS;18.1"
"overallStatus":"USER_ERROR"
"error":"ZONE_NOT_FOUND"
"requestId":"738513AC-9326-42DE-B4E2-DA51F6462943"
"executionTimeMs":"53"
"interfaceType":"NATIVE"
}

Any pointers are greatly appreciated! Bastiaan

CloudKit not updating schema and not syncing after schema change
 
 
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