Can you verify if you have curl_debug set to true or false in your code?
Also please email me your username to email@example.com so I can look into any account issues.
Thanks for forwarding us your username. I reviewed your account and found the approval process for the Scheduling API was completed but not fully propagated yet until this morning. You should be all set now to use the Schedule API.
Also, having debug set to false is why you were not receiving an error message. Setting this to true will help when troubleshooting issues.