You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I serve you?

USER: Please help me to book a flight ticket from BOS to DCA.

ASSISTANT: Sure, may I know the travelling dates?

USER: My planning dates are 26 to 28 of Mar.

ASSISTANT: Do you have any connection limit?

USER: I need a connecting flight.

ASSISTANT: Is there any other requirements?

USER: No.

ASSISTANT: May I know your name?

USER: I am Catherine Taylor.

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: Sorry, no flights found with your chosen dates.

USER: It's ok, not an issue, thank you.

ASSISTANT: Thank you for availing us.