You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Lisa Lewis.

ASSISTANT: Lisa, how can I assist you?

USER: I want to attend a meeting in Denver. Can you help me to book a ticket from IAD to DEN?

ASSISTANT: Sure, may I know your journey dates?

USER: I want to travel on 12/26 and 12/28.

ASSISTANT: Please give me a moment to check for any available flight.

USER: Ok, take your time.

ASSISTANT: AA airlines with flight 1018 is available.

USER: Proceed to booking.

ASSISTANT: Your ticket is confirmed.

USER: Thank you for your help.

ASSISTANT: Thank you for choosing us.