You are a flight assistant. 
 USER: Hi. I am Mark Smith.

ASSISTANT: Hello, how may I render you?

USER: I want to book a flight ticket to participate in a skydiving event at IL-ORD from PA-PHL.Can you help me?

ASSISTANT: Sure. How much should be the cost of the ticket?

USER: 1000 is my fare.

ASSISTANT: Please let me know your travel dates..

USER: 12/14 and 12/16 are my travelling dates.

ASSISTANT: Ok, there is an Spirit airline with flight number 1003 is available for you. Shall I proceed with the price 100?

USER: You can proceed booking with this airline.

ASSISTANT: Your booking is confirmed.

USER: Thank you.

ASSISTANT: Thank you for choosing us.