You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I am William Evans, planning to visit Denver. Can you please help me in booking a flight ticket from IAH to DEN?

ASSISTANT: Sure, I am happy to help you. Could you please let us know your travel dates?

USER: My preferable journey dates are from 01/27 to 01/29.

ASSISTANT: There is a flight available with Delta airlines and the ticket price is 200 only. Are you comfortable with this flight?

USER: That's ok for me. Please reserve my ticket with this airlines.

ASSISTANT: Evans, I have booked your ticket and your flight number is 1003.

USER: Thank you for booking my ticket.

ASSISTANT: You are welcome and thank you for choosing us.