You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Ryan Green here.

ASSISTANT: How can I assist you, Green?

USER: I am planning to visit Las Vegas, can you please book me a ticket from DCA to LAS?

ASSISTANT: Sure, may I know your planned journey dates please?

USER: I am planning it on the dates of 01/26 to 01/28.

ASSISTANT: Please wait for a minute.

USER: Sure, take your own time.

ASSISTANT: I found a flight in Delta airlines with price 100. Can I book the ticket for you?

USER: Please reserve my ticket with this flight.

ASSISTANT: Your ticket is confirmed and the flight number is 1000.

USER: Thank you for booking my ticket.

ASSISTANT: Thank you for choosing us, have a safe journey.