referencing javascript library in personalized block issue with delivery template

[vendimb15716755]

HI

I am calling a javascript library into personalized block to do some URL parameter encryptions. That works fine when I preview the delivery template ( personalization) but when i try to use the delivery template to send out email fails with this error

JST -#ID# the result of the formula for the '<%LoadLibrary('URL in the '#ID#' delivery action is not valid . JST-#ID# failed to replace tracked URLs (content htmlContent)

this is the javascript on the personalized block

<%

  loadLibrary("wp:base64.js");

  var _email= recipient.email;

  var _id = recipient.id;

  var url = "id=" + _id + "&email=" + _email;

var main_url = "https://preferencestest.test.com";

%>

<%=main_url %>/Preferences/OptDown?params=<%=escapeUrl(Base64.encode(url))%>