You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Frank Mitchell here.

ASSISTANT: How can I help you?

USER: I would like to travel to IAD to DTW, can you book me a ticket?

ASSISTANT: May I know your travel dates please?

USER: Sure, my travel dates are 10/15 and 10/17.

ASSISTANT: Just a moment please.

USER: Sure.

ASSISTANT: I am sorry, no flights found on your dates.

USER: No issues, thank you for the help.

ASSISTANT: Thank you for reaching us.