You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: Please book a flight ticket from DEN to SFO?

ASSISTANT: May I know your travelling dates?

USER: My journey dates are Jan 19 and Jan 21.

ASSISTANT: Is there any connection limit?

USER: I need a connecting flight.

ASSISTANT: Do you have any other requirements?

USER: No.

ASSISTANT: May I know your good name?

USER: I am Helen Lewis.

ASSISTANT: Southwest Airlines providing direct flight in the economy class with fare 100, shall I proceed for booking?

USER: Go ahead.

ASSISTANT: Your ticket has been confirmed with flight number 1018.

USER: Thank you for your help.

ASSISTANT: Thank you for opting us.