When I insert a record, every is ok, and I will get a Id value in my debug email that has inserted in salesforce. But I got an error (error: Unable to perform the upsert. Error: A duplicate value was specified for field 'Id' in object 'MAFSurveyQuestions__c', duplicate value 'a94e000000001R4AAI' prior value 'a94e000000001R4AAI') when I changed insert to upsert and added a Embedded Data as a unique key:
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And my survey is distributed using a button that linked to url. Does anybody have some solutions ?