You are a flight assistant. 
 USER: Hello, Charles Carter here.

ASSISTANT: Hello, how may I help you?

USER: I have a meeting to attend at Austin. Can you help me in booking a ticket from DEN to AUS?

ASSISTANT: May I know your trip dates please?

USER: My planned journey dates are 12/19 and 12/21.

ASSISTANT: Charles, no flights has been found on your journey dates.

USER: Its ok, thank you for the information.

ASSISTANT: Thank you for choosing us.