You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am David Carter.

ASSISTANT: David, how may I help you?

USER: My date of travelling is on DEN to ORD, can you in booking?

ASSISTANT: Please share your journey dates.

USER: My date of travelling is on 02/14 to 02/16.

ASSISTANT: Please hold on for a while.

USER: Sure.

ASSISTANT: Sorry, no flight is available on your route.

USER: That's ok. Thank you for your help.

ASSISTANT: Thank you for choosing us.