You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you?

USER: I need to book a ticket from DCA to OAK. Could you book a ticket?

ASSISTANT: Sure, may I know the travelling dates?

USER: Depart is by Mar, 29 and return date is Mar, 31.

ASSISTANT: Do you have any connection limit?

USER: I would prefer connecting flight.

ASSISTANT: Is there any other requirements?

USER: No, thanks for asking.

ASSISTANT: May I know your name?

USER: My name is Samantha Roberts.

ASSISTANT: Please wait a minute.

USER: Sure.

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

USER: Thank you.

ASSISTANT: Thank you for opting us.