External authorization with SmartThings is currently broken for several of the major integrations. SmartThings is actively working on it. (This is impacting IFTTT, Amazon Echo, SharpTools, SmartRules, etc)
Edit: Local device control was not working for third party SmartApps. It looks like the Echo was able to complete the authorization, unlike other SmartApps (more info), but may have been impacted by the inability to control local devices.