The redirect URI in the request, http://potanist.app/accounts/google/login/callback/, does not match the ones authorized for the OAuth client. To update the authorized redirect URIs, visit: https://console.developers.google.com/apis/credentials/oauthclient/946778806868-7jnk9a1cklsn0n9lne9f2lae7oklbqin.apps.googleusercontent.com?project=946778806868