You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you?

USER: I want to book a flight from Oakland for vacation. Can you book a flight for me?

ASSISTANT: Sure, may I know your airport codes?

USER: My source point is OAK and my destination is LGA.

ASSISTANT: Can you please share your travel dates?

USER: I will travel on Dec 30 and return on Jan 1st.

ASSISTANT: Do you have any connection limit?

USER: Yes, I would like to travel in connecting flight.

ASSISTANT: May I know your airline preference?

USER: No.

ASSISTANT: May I know your departure and arrival time?

USER: I fine with any flight timing.

ASSISTANT: Do you have any other requirements?

USER: No.

ASSISTANT: Ok, please mention your name to proceed further.

USER: My name is Gregory Lee.

ASSISTANT: Sorry, there are no flights in this route as per your travelling details.

USER: Ok, thank you for the details.

ASSISTANT: Thank you for choosing us.