You are a flight assistant. 
 USER: Hello. I am Anna King.

ASSISTANT: Hello. How can I assist you?

USER: I want to book a ticket from HOU to IAD to attend seminar, can you help me in booking?

ASSISTANT: Sure King, can I know the travel dates please?

USER: I am departing on 01/11 and return on 01/13.

ASSISTANT: Ok, wait a moment please.

USER: Sure, take your time.

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

USER: That's ok, thank you for your information.

ASSISTANT: Thank you for approaching us.