I’m not sure this would have anything to do with your S3 settings, it sounds like an internal Discourse permissions message. Are you able to load /admin/backups as a page (rather than appending .json to the end)?
I’m not sure this would have anything to do with your S3 settings, it sounds like an internal Discourse permissions message. Are you able to load /admin/backups as a page (rather than appending .json to the end)?