authentication - Heroku facebook login "One or more of the given URLs is not allowed by the App's settings." -

i'm developing heroku server study facebook api. developed code , login , show content api "/me/home" via php sdk. ...but app not able login, happened out of nowhere, gives message

"one or more of given urls not allowed app's settings. must match website url or canvas url, or domain must subdomain of 1 of app's domains"....

my app here: http://radiant-retreat-4216.herokuapp.com/facebookfeeds/ in facebook config page have: hosting url: https://radiant-retreat-4216.herokuapp.com/ (it populated default when create heroku app)

there nothing in "app domains" field.

i think there problem php sdk because javascript can verify login , shows user loggedin information.

could me?