You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Can you book a ticket for me?

ASSISTANT: Sure, could you please provide me your travel dates?

USER: I want to travel on 12/06 and 12/08. I want to travel from CA - LAX to PA - PHL.

ASSISTANT: Do you have any other requirements?

USER: The price limit is 5000.

ASSISTANT: May I know your name for record purpose?

USER: Ronald Martin.

ASSISTANT: I'm sorry to say, there are no flights on your preferable dates.

USER: OK. Thank you for the help.

ASSISTANT: Thank you for reaching us. It's my pleasure.