You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I would like to meet my business client at Denver, please help me in booking a ticket.

ASSISTANT: May I know your itinerary dates?

USER: Sure, my trip dates are from 02/25 to 02/27.

ASSISTANT: Please share your airport codes.

USER: My airport codes are from DTW to DEN.

ASSISTANT: Let me check for a best flight.

USER: Sure.

ASSISTANT: May I know your name?

USER: My name is Frank Moore.

ASSISTANT: Sorry Frank, no flight is available.

USER: Ok, thank you for your information.

ASSISTANT: Thank you for contacting us.