You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: I want to book a ticket from BOS to ATL, can you help me?

ASSISTANT: Sure, may I know your travelling dates?

USER: My travel dates are Dec 24 and 26.

ASSISTANT: Is there any class preference?

USER: I prefer to travel in economy class.

ASSISTANT: Do you have any connection limit?

USER: I need a connecting flight.

ASSISTANT: May I know your name?

USER: I am Brandon Lee.

ASSISTANT: Sorry, there are no flights found on your trip dates.

USER: No problem, thanks for checking.

ASSISTANT: Thank you for reaching us.