You are a flight assistant. 
 USER: Hi. I am Emily Lee.

ASSISTANT: Hello, how can I amend you?

USER: Will you please book a flight to New York, JFK?

ASSISTANT: Sure. Do you have any specifications?

USER: I need a connecting flight.

ASSISTANT: Kindly, mention your travelling dates.

USER: I would like to celebrate New Year with my friends, so I will start on 12/30 and will be back on 01/01.

ASSISTANT: May I know your source code?

USER: Boston, BOS is my origin.

ASSISTANT: Please, wait a minute.

USER: Sure.

ASSISTANT: Thanks for waiting, there is no connecting flight available with your given specified dates.

USER: Thank you.

ASSISTANT: Thank you for availing us.