You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am Carolyn Mitchell. I would like to visit SFO to meet my brother, can you please help me to book a flight ticket from BOS?

ASSISTANT: May I know your journey dates?

USER: Sure, my travelling dates are Mar 26 and Mar 28.

ASSISTANT: Is there any connection limit?

USER: I need a connecting flight.

ASSISTANT: Is there any class preference?

USER: No.

ASSISTANT: May I know your departure and return timings?

USER: My departure and return time is afternoon.

ASSISTANT: Ok, please wait for a moment.

USER: Sure, take your own time.

ASSISTANT: We regret to inform you that, there are no flights moving to your region with your planned dates of travelling.

USER: No problem, thank you for your information.

ASSISTANT: Thank you for choosing us.