You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you at this moment?

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

ASSISTANT: Ok, I am here to help you with that. Can I know your planned trip dates?

USER: I am departing on Oct 14 and return on Oct 16.

ASSISTANT: Can I know your connection limit?

USER: I prefer a connecting flight which depart in evening.

ASSISTANT: Ok, may I know your name?

USER: My name is Sandra Phillips.

ASSISTANT: Ok, wait for a minute.

USER: Sure.

ASSISTANT: Sorry to say that, there are no flights available based on your journey dates.

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

ASSISTANT: Thank you for approaching us.