Error fetching buckets: Access Denied

I am repeatedly getting Error fetching buckets: Access Denied when trying to configure the plugin. I have added the defined globals in wp-config.php and added the policy to the bucket following the policy generator on http://awspolicygen.s3.amazonaws.com/policygen.html and https://docs.aws.amazon.com/AmazonS3/latest/dev/example-bucket-policies.html. I can’t resolve this.

Using PHP 5.6.2, curl 7.28.1

https://wordpress.org/plugins/amazon-s3-and-cloudfront/