I had a custom domain on my Confluence site with the trial, but I removed it. The admin panel now shows the default <org>.atlassian.net, but when I go to <org>.atlassian.net/wiki, it redirects me to <custom_domain>/wiki - which is no longer valid.
You'll be best off opening a ticket with Atlassian. Since this is still in beta there isn't a lot we can suggest.
You must be a registered user to add a comment. If you've already registered, sign in. Otherwise, register and sign in.