Form (rendered field) not working on Custom Content Type

Hi all,

I made a custom themed D8 site which is working great. I’ve made some custom content types so the people at my company can post jobs and internships.
These types have their own node twig files to make them custom where I add the fields in my custom layouts.

I made several contact forms with their own fields and email to send it to. My content editors can choose which form to add to the job page. The form is a referenced field to Contact Form and I output it as a Rendered Identity. –> My twig file can output it as {{ content.field_contact_formulier }}

So it all works great, except for the fact that when I try to submit the form, it just doesn’t work.
At the moment I just implemented the good old “mailto:” links but I do want my form to work.

Any tips on this strange issue? Thanks in advance!

Drupal version: 


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