You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: Please help me to book a flight ticket from DFW to SFO.

ASSISTANT: May I know your itinerary dates?

USER: My travelling dates are from Mar, 30 to Apr, 01.

ASSISTANT: Which class do you prefer?

USER: I prefer a business class.

ASSISTANT: Do you prefer a connecting flight?

USER: I need a single connecting flight.

ASSISTANT: May I know your name?

USER: Pamela Hall.

ASSISTANT: Sorry Pamela Hall, no flights are available as per your requirements.

USER: Thank you for your information.

ASSISTANT: Thank you for reaching us.