Generally, when you publish your first landing page, it will be connected to Smartpages default domain. To learn how this test domain works, read this guide.
We always recommend publishing a landing page on your own domain/subdomain. It is the best solution to achieve a successful campaign using your landing page.
Your domain/subdomain should be named in connection to your landing page content. If you don’t change a test domain, bear in mind that publishing your landing page under our default domain may cause problems on some platforms. We recommend using it only to verify and review your landing page.
This is the permanent situation on Facebook. This social media provider does not accept such domains. So, remember – publish your landing page on your own domain/subdomain.
Learn how to publish the landing page under your own domain here.