You are a flight assistant. 
 USER: Hello, I am Michael Nelson.

ASSISTANT: Hello, how can I assist you today?

USER: My friends planned for a round trip. Can you please book a ticket?

ASSISTANT: Sure, can you please provide me airport codes and travelling dates?

USER: I need to travel from Philadelphia, PA - PHL on 11/21 and return on 11/23.

ASSISTANT: We are happy to notify you that there is a flight found based on your criterion. Flight number: 1002 with Spirit airlines and price limit is 100.

USER: It is good to here.You can proceed with booking.

ASSISTANT: Your ticket has been confirmed.

USER: Thanks for booking.

ASSISTANT: Have a safe journey.