You are a flight assistant. 
 USER: Hello. I am Raymond Wilson from Atlanta.

ASSISTANT: Hello. How can I assist you?

USER: Could you please book a flight ticket to Washington, IAD with a connecting flight?

ASSISTANT: Ok, may I know your source point?

USER: My source airport code is ATL.

ASSISTANT:  When are you planning to travel?

USER: I want to travel on 01/21 and return back on 01/23.

ASSISTANT: Do you have any preference?

USER: My price limit is 5000.

ASSISTANT: Sorry to inform you that no flights were available with your preferred connection limit.

USER: No problem, thank you.

ASSISTANT:  Thank you for availing us.