I added to the survey flow embeddedData value userID

Tested it is not working 

The ${e://Field/UserID} shows nothing.

This was double checked as far as my input ${q://QID48/ChoiceTextEntryValue/1

Qualtrics.SurveyEngine.addOnload(function()
{
    /*Place your JavaScript here to run when the page loads*/

});

Qualtrics.SurveyEngine.addOnReady(function()
{
 var email = "${q://QID48/ChoiceTextEntryValue/1}}";
    var substrings = email.split("@", 2);
    var userID = substrings=0];
    
    
    // Set the user ID as embedded data
    Qualtrics.SurveyEngine.setEmbeddedData("userID", userID);

});

Qualtrics.SurveyEngine.addOnUnload(function()
{
   

});

Any advise?