I'm trying to use the following code below with the HTML Block but it is not working. Any help or suggestions?

<div id="AmazonPayButton"/>
<script type="text/javascript">
var authRequest;
OffAmazonPayments.Button("AmazonPayButton", "YOUR_SELLER_ID_HERE", {
type: "LwA",
useAmazonAddressBook: true,
authorization: function() {
loginOptions =
{scope: "profile payments:widget payments:shipping_address"};
authRequest = amazon.Login.authorize(loginOptions);
},
onSignIn: function(orderReference) {
// The following OAuth 2 response parameters will be included in
// the query string when the customer's browser is redirected to
// the URL below: access_token, token_type, expires_in, and scope.
authRequest.onComplete("/redirect_page?session="
+ orderReference.getAmazonOrderReferenceId());
},
onError: function(error) {
// your error handling code
}
});
</script>