I had the same issue, I had retrieved the container via: let container = CKContainer.default() spent a few hours one day working on it, then the following morning decided to try: let container = CKContainer(identifier: "mycontainer.id") and it worked. So I tried print the default container identifier, which turned out to be mycontainer.id -- so I reverted my code to: let container = CKContainer.default() and it worked again. My conclusion is that either: calling it with the identifier explicitly fixed some setting, to make it match the setting in the XCode project settings (which had always been mycontainer.id), or: there was an issue where Apple had to finish updating some database permissions or something internally, which took a few hours or more (less than a day in my case though thankfully). Anyway, figured I'd post this in case for when someone else runs into it -- seems to be a reasonably common issue.

I had the same issue, I had retrieved the container via: let container = CKContainer.default() spent a few hours one day working on it, then the following morning decided to try: let container = CKContainer(identifier: "mycontainer.id") and it worked. So I tried print the default container identifier, which turned out to be mycontainer.id -- so I reverted my code to: let container = CKContainer.default() and it worked again. My conclusion is that either: calling it with the identifier explicitly fixed some setting, to make it match the setting in the XCode project settings (which had always been mycontainer.id), or: there was an issue where Apple had to finish updating some database permissions or something internally, which took a few hours or more (less than a day in my case though thankfully). Anyway, figured I'd post this in case for when someone else runs into it -- seems to be a reasonably common issue.

Hiding containers sounds like a great compromise for whatever limitations there are that have caused deleting to not be supported.