You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello. How can I aid you?

USER: I am David Green. I need to schedule my trip to Philadelphia to meet my fiance. Can you please help me booking the flight ticket from LAX to PHL?

ASSISTANT: Sure.

USER: Thank you.

ASSISTANT: Can I know your travelling dates?

USER: I am planning to start on 11/20 , my return date would be 11/22.

ASSISTANT: We found a Delta airline, flight number:1020 and the price is 100.

USER: Please, book my ticket.

ASSISTANT: Ok. Your flight ticket has been reserved.

USER: Thank you for help.

ASSISTANT: Thank you for choosing us.