You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you now?

USER: I want to book a ticket from OAK to PHL, can you help me?

ASSISTANT: Sure, I am happy to help you with that. Can I have your travel dates please?

USER: My travel dates are Dec 29 and 31.

ASSISTANT: Ok, please let me know the airlines preference.

USER: I want to travel in normal cost airline.

ASSISTANT: May I know your name please?

USER: I am David Scott.

ASSISTANT: Please allow me a moment.

USER: I want to travel in business class.

ASSISTANT: Sorry to inform you that no flight is available to you on your dates.

USER: No problem, thanks for checking.

ASSISTANT: Can I have your name please?

USER: I am David Scott.

ASSISTANT: Thank you for choosing us, have a good day.