You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am Anthony Moore. I am planning to book a ticket from OAK to DEN. Can you please help me out?

ASSISTANT: Sure, please tell me your trip dates.

USER: I would like  to travel on 12/24 an return on 12/26.

ASSISTANT: Sorry, no flight is there to reserve a seat for you.

USER: That's fine. Thank you for your help.

ASSISTANT: Thank you for choosing us.