You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Dorothy Adams here.

ASSISTANT: How may I help you today?

USER: I would like to prefer a flight with lay-by option for my business trip to Denver. Can you book the flight ticket?

ASSISTANT: Sure, I am here to help you with that. Can I know your planned trip dates?

USER: The travel dates are from May 25 to May 27.

ASSISTANT: Can I know your good name?

USER: I am Dorothy Adams.

ASSISTANT: May I know your airport codes?

USER: The airport codes are from IAD to DEN.

ASSISTANT: Is there any other requirements?

USER: No.

ASSISTANT: Please wait for a minute.

USER: Sure.

ASSISTANT: There is a flight ticket which is a economy class in the Southwest  Airlines, the ticket cost is 100 and the connection limit is one. Shall I reserve the ticket?

USER: I am fine with the airlines. You can book it.

ASSISTANT: Your ticket is confirmed in an economy class and the flight number 1021.

USER: Thank you.

ASSISTANT: Thank you for approaching us. Have a safe journey.