get_secure_attachment_url not working

I used this code:
$id=<<post id>>;
global $as3cf;
$url = $as3cf->get_secure_attachment_url($id);

And got this url:
http://floralegacy.s3.amazonaws.com/files2/146/14671.pdf?AWSAccessKeyId=AKIAJBABBTNK7O4RV6WA&Expires=1397401696&Signature=DH2NuM1r%2B4casctJY4kxyvzi4D8%3D

But when I try to use it (via code, fopen with the URL created), I get this message:
Warning: fopen(http://floralegacy.s3.amazonaws.com/files2/146/14671.pdf?AWSAccessKeyId=AKIAJBABBTNK7O4RV6WA&Expires=1397401696&Signature=DH2NuM1r%2B4casctJY4kxyvzi4D8%3D) [function.fopen]: failed to open stream: HTTP request failed! HTTP/1.1 403 Forbidden in /home (…)

And when I open the generated URL in the browser:
<Error>
AccessDenied
<Message>Access Denied</Message>
<RequestId>EAA7FF577BA73AF5</RequestId>
<HostId>
SvRCVP8L+XBj54m3JohqBO1nJypU46DM7sSxc7om4tcIhmOVmkJkJalRdFRtAz50
</HostId>
</Error>

My bucket has a policy that prevents hotlinking, but to my understanding this should not affect a secure URL, and any case this code is being executed on a server that’s permitted in the policy (both flora.org.il and localhost:8080):
{
“Version”: “2008-10-17”,
“Id”: “HTTPreferrerpolicy”,
“Statement”: [
{
“Sid”: “1”,
“Effect”: “Deny”,
“Principal”: {
“AWS”: “*”
},
“Action”: “s3:GetObject”,
“Resource”: “arn:aws:s3:::floralegacy/*”,
“Condition”: {
“StringNotLike”: {
“aws:Referer”: [
“http://blog.flora.org.il/*&#8221;,
“http://flora.org.il/*&#8221;,
“http://localhost:8080/*&#8221;
]
}
}
}
]
}

Any help would be much appreciated.

https://ww.wp.xz.cn/plugins/amazon-s3-and-cloudfront/