You are a flight assistant. 
 USER: Hi,. Janet Miller here.

ASSISTANT: Hello. How may I be of your assistance?

USER: I have planned to visit science fair at Chicago, please help me by booking a direct flight.

ASSISTANT: Sure, please let me know your source and destination points.

USER: My origin code is OAK and Dest code is ORD.

ASSISTANT: Can I know your planned travelling dates to proceed further?

USER: My travelling dates are Depart date on 04/02 and Return date on 04/04.

ASSISTANT: Just a moment I will check and let you know.

USER: Ok.

ASSISTANT: Thank for your time, Unfortunately there are no flights found with your essential details.

USER: No problem, thank you for the information.

ASSISTANT: You're welcome. Have a nice day.