Error

We're sorry, your request was malformed or was unable to be completed for some reason. Try hitting the back button and restarting the process to see if it fixes the problem.

If you want the nerdy explanation, review the following JSON body.
{
  "error" : "invalid_request",
  "error_description" : "The post_logout_redirect_uri is invalid.",
  "error_reason" : "invalid_post_logout_redirect_uri"
}