Often times this happens when you have been working on your staging url (.webflow.io) then attempt to work with Zapier on a task without updating the “live” CMS on your custom domain. The problem is as the error says, which means you have to publish to all domains in your publish menu before working with Zapier…if you have previously published to all domains prior. I realize this might not be an ideal situation because maybe you’ve made many other changes to your site and you don’t want those changes published “live” just yet but do need to get this Zapier integration to work.