Ok, so after some digging, what stops me is the Restlet authentication. You can do it using a facebook webhook, which require an endpoint on your server. Facebook doesn't include an option to add a header, you just provide a URL https://developers.facebook.com/docs/marketing-api/guides/lead-ads/quickstart/webhooks-integration/ Authentication happens using a verification token (a different process) So a Restlet won't work, because it requires authentication. So the solution is to disable authentication on the Restlet, which I think it is not allowed, or to pass the authentication data as query parameters, which also I don't think NS will recognize.