Meaning of "Cycle detected in record graph"?

I can't understand why this error appears when I'm trying to save my record to the iCloud.


Optional(<CKError 0x15c6faae0: "Invalid Arguments" (12/1007); "Invalid list of records: Cycle detected in record graph">)


Can anyone help me with what is likely causing this error?

I got this error and I relized that I had created a CKReference object using the same CKRecordID as the object I was adding it to. I had used the CKRecordID of the actual object instead of the CKRecordID of the referenced object when creating the CKReference.

Meaning of "Cycle detected in record graph"?
 
 
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