You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Carol Jackson.

ASSISTANT: How can I assist you?

USER: Can you please help me  to book a flight ticket  from IAD to DCA?

ASSISTANT: Sure Carol, can I know travel dates please?

USER: My departure and arrival dates are 08/02 and 08/04.

ASSISTANT: Ok, wait a moment please.

USER: Ok.

ASSISTANT: Sorry, there are no flights available on your dates.

USER: It's ok, thank you for checking.

ASSISTANT: Welcome.