I have installed a plugin for workpress called dynamicwp-contact-form.
I needed to remove some fields because i only need input for name an phone number. But there is also a piece of js script that handles the submit and this still counts on the fields to be there.
So a small js script change.
you can see my site at sens-a-web.nl. its the blue 'bel me' button hovering on the left
let me know asap