You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I assist you?

USER: Can you please book me a ticket from PHX to IAD?

ASSISTANT: Sure, I will help you in booking. Can you please share your trip dates?

USER: My travel dates are from May 23rd to May 25th.

ASSISTANT: May I know your name to proceed further?

USER: I am Betty Carter.

ASSISTANT: Betty Carter, regret to inform that there are no flights found on this route for the given dates.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us.