What does the AWS AppSync graphql error mean when attempting to add a custom primary key using amplify push?

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The AWS AppSync GraphQL error when attempting to add a custom primary key using Amplify push usually means that there is a conflict between the existing data and the new schema. This error can occur if there are records in the database with the same ID as the new custom primary key you are trying to add. In order to fix this error, you may need to remove or modify any existing records with the conflicting ID in order to successfully add the new primary key. Another potential solution is to use a different primary key that does not conflict with existing data.