You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: Please book me a flight ticket from IAD to SEA.

ASSISTANT: Sure, I can help you with that. May I know your travel dates please?

USER: I will start on Aug 19th and return on Aug 21st.

ASSISTANT: Do you need break in between your journey?

USER: I need 1 lay by.

ASSISTANT: Please let me know if you have any other specifications.

USER: I am fine with above essentials.

ASSISTANT: May I know your good name please?

USER: I am Dennis Walker.

ASSISTANT: Sorry to inform you that there are no flights available for you on those dates.

USER: That's alright, thanks for your assistance.

ASSISTANT: Thank you for choosing us.