Get emails of users from the email field of Hubspot contact from - wordpress

Question

On my WordPress website I have a contact form built in Hubspot. I got the script of this form from Hubspot and past it in my contact page (https://stagezero.ai/contact/).
<script>
hbspt.forms.create({
region: "na1",
portalId: "20085053",
formId: "412d2c51-95f1-4a6c-b3f3-f71c5852ac98"
});
</script>
Whenever the form is submitted the user is redirected to our thank you page (https://stagezero.ai/thank-you/).
So, whenever someone submit the form I want to extract the Emails of our users from the email field on our contact from. So basically, the goal is to get the emails stored as a variable so that it can be hashed and sent to google analytics.
I have tried to do it by myself by writing and pasting this code in my contact page but unfortunately it did not work. Can some help me to achieve the goal which I have mentioned above?
Thank you.
<script>
//code to get email values from contact form’s email field
var form = document.getElementById("hsForm_412d2c51-95f1-4a6c-b3f3-f71c5852ac98");
var email_field=document.getElementById("email-412d2c51-95f1-4a6c-b3f3-f71c5852ac98");
form.onsubmit = function(){
var email = email_field.value();
//code to send email values to Google Analytics
dataLayer.push({
'event':'form_submit',
'enhanced_conversion_data': {
"email": email // replace 'yourEmailVariable' with email variable //
}
});
};
</script>