You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you today?

USER: Could you help me in booking a flight ticket from DCA to IAD?

ASSISTANT: Sure, let me know your journey dates.

USER: I want to fly on Dec 18, return on Dec 20.

ASSISTANT: Ok, please share your connection limit.

USER: I want a flight with one connection.

ASSISTANT: Is there any class preference?

USER: I want a business class flight ticket.

ASSISTANT: Can I have your name please?

USER: My name is Sandra Smith.

ASSISTANT: Do you have any specifications to meet?

USER: No.

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT: Thanks for your time, no flights were found based on your schedule.

USER: Not an issue, thank you.

ASSISTANT: Thank you for availing us.