Have you tried to re-authenticating your test account?
go to https://api.twitch.tv/kraken/oauth2/authorize?response_type=token&client_id=YOUR_CLIENT_ID&redirect_uri=YOUR_REDIRECT_URL&scope=channel_editor
It should redirect you to your website example.com/callback#access_token=j2k3b42b34jhb3h4bj234bhj234&scope=channel_editor
set your YOUR_OAUTH_TOKEN to match the access token, in this case j2k3b42b34jhb3h4bj234bhj234
and try it.