Sending data with onFormSubmit: data being sent only for existing contacts

Marketing & Content Hub Lead Capture Tools
1

Hi there!

I’m trying to send data through my HB form using hidden fields. We’re testing the form with my team and it seems like if the person hitting submit is already a HB contact, then the function inside onFormSubmit runs fine and we get an email with the data we want, but if the person isn’t already a HB contact, we just get a regular email with the person’s email address (which is the only non-hidden field in the form).
Any idea what this could be?
I’ll leave my code in the comments as it seems to mark my post as spam if I put it here.

2 
 hbspt.forms.create({
 portalId: "2961853",
 formId: "b9bc4c6d-ce95-4275-ac7c-1ca703211196",
 onFormSubmit: function($form) {
 const form = $form[0]
 const email = form[0].value
 const companySize = $('#slider')[0].value
 const paymentPeriod = annually.prop('checked') === true ? 'annually' : 'monthly'
 const currency = $('.currency')[0].innerHTML
 const total = $('#final-price')[0].innerHTML
 const data = {
 fields: [
 {
 name: "builder_company_size",
 value: companySize
 },
 {
 name: "builder_payment_period",
 value: paymentPeriod
 },
 {
 name: "builder_currency",
 value: currency
 },
 {
 name: "builder_price",
 value: total
 },
 {
 name: "email",
 value: email
 }
 ],
 legalConsentOptions: {
 consent: { // Include this object when GDPR options are enabled
 consentToProcess: true,
 text: "I agree to allow Starred to store and process my personal data.",
 communications: [
 {
 value: true,
 subscriptionTypeId: 999,
 text: "I agree to be contacted by Starred."
 }
 ]
 }
 }
 }
 $.ajax({
 type: "POST",
 url: 'https://api.hsforms.com/submissions/v3/integration/submit/2961853/b9bc4c6d-ce95-4275-ac7c-1ca703211196',
 data: JSON.stringify(data),
 success: 'success',
 dataType: 'json',
 contentType: 'application/json'
 });
 }
 });