Upload file to Basin doesn't work

Hi there,

Im creating a form that is link to a free Basin account of mine. Now I also need the ability to upload files in that form. But when I add the upload form element Basin is not receiving the files.
I found this support page on Basin but I have no idea how to use it.

This is my site and the form is in a popup in the footer under the button ‘Odeslat pitch’
https://preview.webflow.com/preview/j-t?utm_medium=preview_link&utm_source=designer&utm_content=j-t&preview=c8a7a28f749d06f94017bcd748aa8c87&mode=preview

Thank you already for taking the time.

So you need to add your credit card to Basin for the 14 days trial. Although it looks like you are already in a trail when you sign up. Then you can receive files from your form to Basin.