You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you for the day?

USER: I want to visit Washington IAD from Boston BOS. Can you find a flight ticket for me?

ASSISTANT: When you are willing to travel?

USER: Ok, my planned trip dates are on Dec 16 and return on Dec 18.

ASSISTANT: Do you have any connection limit?

USER: I need a single connecting flight.

ASSISTANT: May, I know your good name?

USER: Yes, I am Rachel Martin.

ASSISTANT: Do you have any other requirements?

USER: No, I don't have any other requirements.

ASSISTANT: Sorry, we found no flights on your given dates.

USER: Ok, not an problem. Thank you for your information.

ASSISTANT: Thank you for reaching us.