You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: William Collins here. I am looking a flight from Phoenix to Chicago, can you help me in booking my flight?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: May I know your preferable dates?

USER: My travelling dates are 24 Sep and 26 Sep.

ASSISTANT: How much you can afford for this ticket?

USER: My airfare should not exceed 1000.

ASSISTANT: We found a flight on your details with airline Southwest, flight number: 1004. Shall I book this ticket?

USER: Ok, proceed with the booking.

ASSISTANT: Your ticket has been booked.

USER: Thanks for helping me.

ASSISTANT: Thank you.