You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I want to travel from Washington to Chicago.

ASSISTANT: That's good to hear, may I know your airport codes that you want to travel.

USER: My origin airport code is DC-IAD and destination airport code is IL-ORD.

ASSISTANT: OK, may I know your journey dates?

USER: My departure date is 08/11 and return date is 08/13.

ASSISTANT: Sorry, unfortunately there is no flight found in these dates. May I know your name for formalities?

USER: My name is Carol Campbell. Thanks for your help.

ASSISTANT: Thank you for choosing our helpline, have a good day.