https://community.hubspot.com/t5/APIs-Integrations/API-field-names-don-t-correspond-to-Form-UI-field-names/m-p/713398#M58385 <P>We had the same issue.</P><P>&nbsp;</P><P><SPAN>The issue is that Forms behavior changed a few months ago:</SPAN><BR /><A class="" href="https://developers.hubspot.com/changelog/validation-change-to-the-forms-api-submission-endpoints" target="_blank" rel="noopener noreferrer">https://developers.hubspot.com/changelog/validation-change-to-the-forms-api-submission-endpoints</A></P><P><BR /><SPAN>Before, forms didn't require to add Fields (=properties) to them. If the fields were valid, the forms worked. We had a form with no Fields in it, except for the email, so we had complete flexibility in the dev side. It worked.</SPAN><BR /><SPAN>After the change, for forms created from March 22 and onwards, you need to include all relevant fields explicitly in the form.&nbsp;</SPAN></P><P>&nbsp;</P><P><SPAN>Forms older than March 22 should still work with the previous behavior, this is what Hubspot say.</SPAN></P><P><SPAN>But for some reason, it won't work with newer&nbsp;</SPAN><STRONG>fields</STRONG><SPAN>&nbsp;created after March 22, even if the form is older.</SPAN><BR /><SPAN>It's like what they said about the granularity is wrong - it's about the date of the&nbsp;</SPAN><STRONG>fields</STRONG><SPAN>&nbsp;that are used in the form, not the the date of the form itself.</SPAN></P><P>&nbsp;</P><P><SPAN>We added the Field to the old Form (marked it as not required) and it worked. All older Fields that were submitted via the Form without being added, still work. Weird.</SPAN></P> Wed, 02 Nov 2022 16:06:54 GMT advance512 2022-11-02T16:06:54Z