Form submission: set relationship field to current post ID

I have a relationship field in my cpt. I am using dynamic forms to display a form in front page, to create new posts. Is there a way to keep the relationship hidden, and also to set it to the current post ID?

I have tried advanced conditions to hide it, or to set the default value to {current:post:ID} without luck. Hiding it will actually remove it from the form.

By the way, your plugin is like an art form, beautiful, functional, and with vast possibilities which can be made more visible with documentation. Thank you so much.