You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Myself David Harris.

ASSISTANT: Ok.

USER: I would like to visit PHX for visiting the national park their. Can you book a ticket?

ASSISTANT: Sure, can you please provide your travelling dates?

USER: My dates are from 06/25 to 06/27.

ASSISTANT: May I know your source code?

USER: My source code is LAX.

ASSISTANT: The airline JetBlue with flight number 1008 is available.

USER: Sure, proceed with booking.

ASSISTANT: Ok. Your reservation is done.

USER: Thank you for making my reservation.

ASSISTANT: Thank you for choosing us.

USER: You are welcome.