Tags are not populating

The script does not populate certain tags that I am trying to capture. Below is an example copy of my script. (the url has been modified slightly) I am using the tag suggested by your documentation to capture email. In the script below, I am able to capture information from {order_number}, but {customer_email} does not populate any information. I’ve also tried {shipping_email} and {billing_email} both with no luck. Do you know any other parameters that might pass an email forward other than {customer_email}? That parameter doesn’t seem to pass anything. Any help would be greatly appreciated!

<script type=”text/javascript”>
window.rrSpace = (
rrSettingsReferralUpdate = {
debug: “false”,
parameters: {
referralkey_email: “{customer_email}”,
externalidentifier: “{order_number}”
}
}
);
(function (f, r, n, d, b, y) { b = f.createElement(r), y = f.getElementsByTagName(r)[0]; b.async = 1; b.src = n; b.id = ‘RR_DIVID’; y.parentNode.insertBefore(b, y); })(document, ‘script’, ‘//example.example.com/webpixel/beta/universalv03.js’);
</script>`