You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: I would like to book a ticket from LAX to SFO. Could you book a ticket?

ASSISTANT: May I know your travel dates?

USER: Travelling dates are from Dec, 28 to Dec, 30.

ASSISTANT: Do you have any connecting limit preferences?

USER: I would be comfortable with single stop over.

ASSISTANT: Do you have any other preferences?

USER: I prefer economy class.

ASSISTANT: May I know your name please?

USER: My name is Gary Allen.

ASSISTANT: No flights found as per your preferences at the moment.

USER: Thank you.

ASSISTANT: Thank you for choosing us.