I am using domain mapping with multisite and I am unable to preview changes using the mapped domain

On my multisite install, I am using subdomains while a site is under construction and then using the mapped domain when it goes live. However, once I am using the mapped domain and I try to make changes to a page and use the Preview Function to look at the changes before publishing, I get an error message that I do not have permission to preview on the site. I am the superadmin on the main site and I am admin on the sub-site. Is this a configuration issue? I couldn't find anything in the docs or in the Community page.

Thanks!