You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

USER: I am looking to book a flight ticket from OAK to DEN. Can you help me for that?

ASSISTANT: Sure, I am here to help you. May I know your travel dates please?

USER: My travelling dates are Dec 03 and Dec 05.

ASSISTANT: Ok, do you have any specifications?

USER: I prefer to book a single connecting flight.

ASSISTANT: Ok, hold on for a moment. Let me check the best available flight for you.

USER: Sure, I will wait for your response.

ASSISTANT: I found a flight for you with Spirit Airlines and it costs you 100. Shall I proceed?

USER: Ok, proceed for booking.

ASSISTANT: On whose name you would like to book this ticket?

USER: My name is Karen Lewis.

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

USER: Thank you for booking.

ASSISTANT: Welcome, thank you for choosing us. Have a safe flight.