Internal server error - custom dashboard page

I got a internal server error everytime when opening a custom dashboard page. The GET-Request https://manage.wix.com/_api/admin-pages-server/site/token/ fails with the 500 internal server error. Error-Code in Response-Body is -100.
I visited the site as a contributor.

  • The error occurs independently of the page content
  • The error occurs occurs independently of the browser
  • The page doesn’t continue to load $w.onReady is never fired.
    Any ideas how to fix this problem?