S3 Access Denied issue

Please check if you have any bucket policies restricting the same. You need to allow s3:GetObject in your IAM policy or S3 bucket policy. Below is an example.

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "s3:GetObject"
            ],
            "Resource": [
                "arn:aws:s3:::mybucket",
                "arn:aws:s3:::mybucket/*"
            ]
        }
    ]
}

How do I troubleshoot 403 Access Denied errors from Amazon S3? https://aws.amazon.com/premiumsupport/knowledge-center/s3-troubleshoot-403/?nc1=h_ls

If you still face issue after this, check CloudTrail for the corresponding API call from quicksight and you will be able to identify the hurdle.