You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I serve you today?

USER: Myself Robert King. One of my close friend is hospitalized and I need to see him, so please book me a ticket with single connection.

ASSISTANT: Sure, please share me your journey dates.

USER: I will go on 06/24 and return back on 06/26.

ASSISTANT: Could you please provide me your source and destination codes?

USER: It's a round trip to Washington, IAD.

ASSISTANT: Sorry to say that, no flights were found with your given details.

USER: Ok, no problem. Thank you for your time.

ASSISTANT: Thank you for choosing us.