A new feature was added to the front end of the AWS Backup 'Create/Edit Report' workflow that prompts the user with the correct security principal to allow via the S3 Bucket Policy. I expect that the security principal used was updated but the prompt was not when the new security principal was originally implemented. The backups are now working correctly.
I'm having the same error with a brand new report using the copy/pasted policy for the bucket.
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