You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I abet you?

USER: I am Carol Thompson. I need to book a flight ticket with direct flight, Can you please help me for booking from ORD it's a round trip?

ASSISTANT: Sure, when are you planing to travel?

USER: I would like to travel on 11/30 to 12/20.

ASSISTANT: Ok please wait.

USER: Sure.

ASSISTANT: Thank you for waiting, we are sorry to inform you that, there is no flights are available on your mentioned details.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thank you for choosing our service.