You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: I am looking for a flight from IAD to BOS, can you help me out?

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

USER: My trip dates are from Dec 18th till Dec 20th.

ASSISTANT: Can I have your good name please?

USER: Myself Joshua Garcia.

ASSISTANT: May I know your class and airline preference please?

USER: No.

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

USER: No.

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

USER: That's ok, not an issue. Thank you.

ASSISTANT: Thank you for choosing us, have a nice day.