You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: Will you please book me a flight ticket from ORD to OAK?

ASSISTANT: Sure, I will help you. Please help me with your name.

USER: I am Patrick Allen.

ASSISTANT: Please help me with your planned travelling dates.

USER: I will leave on Sept 11th and return on Sept 13th.

ASSISTANT: Do you need a break in between your journey?

USER: I am looking for a direct flight.

ASSISTANT: Do you have any other preferences in your journey?

USER: I would prefer to travel in a business class flight.

ASSISTANT: Please allow me a minute.

USER: Sure.

ASSISTANT: Patrick Allen, I am really sorry to inform you that there are no flights available for your journey.

USER: That's alright, thanks for checking.

ASSISTANT: Thank you for reaching us. Have a great time.