You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: Can you please help me in booking a flight ticket from PHL to IAD?

ASSISTANT: Sure, let me know your trip dates please?

USER: I want to fly on July 18 and return on July 20.

ASSISTANT: May I know your connection limit?

USER: I need a single connection.

ASSISTANT: Ok, is there any class preference?

USER: I would like to prefer business class.

ASSISTANT: Do you need any other specifications?

USER: No.

ASSISTANT: Can I know your name please to proceed further?

USER: Myself Ruth Brown.

ASSISTANT: Sorry to inform you that there are no flight services available on your given dates.

USER: Not an issue. Thank you.

ASSISTANT: Thanks for contacting us.