You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello.

USER: I am Betty Lee.

ASSISTANT: How can I aid you today?

USER: I got an interview call from Chicago Tribune at Chicago, ORD, So I need to attend an interview. Can you please book a flight ticket for me?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: Could you please provide your travelling dates?

USER: My departure and arrivals dates are, 03/16 and 03/18.

ASSISTANT: May I know your source code?

USER: My source point is Denver, DEN.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Sorry, no flights found on your requested travelling dates. Thank you for approaching us, have a nice day.

USER: Ok, no issue. Thank you.