Assuming you are using a valid Role ARN, you are seeing "message" as blank because your integration is working as expected. Have you tested with an SFTP client? Are you seeing any other indications that tell you it's not working?
Thanks for confirming Smitha, I was under the impression that the Message needed to contain the Role as per the documentation on the AWS site.
I will continue testing on my end with an SFTP client to see if I can get it to work.
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