You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: I am Helen Harris. I need to book a flight ticket from BOS to SFO. Please help me in booking a flight ticket.

ASSISTANT: Yes, can you tell me your travelling dates?

USER: My trip dates are from 08/31 to 09/02.

ASSISTANT: Do you have any other preferences?

USER: I need to depart in the evening and I need a connecting flight.

ASSISTANT: Give me a moment.

USER: Sure.

ASSISTANT: Sorry to inform you that there are no flights found on your requested dates.

USER: No problem, thanks for your information.

ASSISTANT: Thank you for reaching us.