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

ASSISTANT: Hello, may I know how best I can help you today?

USER: I want to book a flight ticket with price under 1000, can you help me with it please?

ASSISTANT: Sure, we can provide you as you requested. May I know your boarding and landing airport codes?

USER: Yes, my boarding and landing points are Seattle, WA-SEA and Philadelphia, PA-PHL.

ASSISTANT: Ok, please help me with your dates of travel?

USER: Sure, my travelling dates are 10/25 and 10/27.

ASSISTANT: 1002 flight in UA airline is available on your route. Shall I proceed to book this flight.

USER: Please proceed with booking.

ASSISTANT: Ok, your ticket has been conformed. And the fare is 100.

USER: Thank you.

ASSISTANT: Thanks for reaching us, have nice day.