Exception "The operation couldn’t be completed" (CKErrorDomain error 3 )

This exception triggers when the app tries to get the instance of the local database. It works well on other devices so far. I've tried 3 different devices with 3 different iOS versions (13, 14.1 and 14.2) And the one having this problem is the one with the 14.1 although I doubt this is an iOS problem.
CKErrorDomain 3 seems to show connectivity problems but the device has good internet connection, also the iCloud is enabled.

Anybody experiencing same issue?
Yes, I am also having this issue. I'm downloading records from CloudKit. It works fine on Wifi but not on mobile data. I have read about the qualityofservice solution on StackOverflow: https://stackoverflow.com/questions/32493698/ios-9-cloudkit-query-does-not-return-anything-while-connected-to-cellular-netwo. But this does not work for me either. Tell me if you have resolved thanks.
Exception "The operation couldn’t be completed" (CKErrorDomain error 3 )
 
 
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