You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. Can you please tell me how can I assist you?

USER: I am planning to visit Denver city, can you please book me a ticket from SEA to DEN?

ASSISTANT: May I know your travel dates?

USER: My preferable journey dates are from 03/22 to 03/24.

ASSISTANT: May I know your name.

USER: My name is Daniel Green.

ASSISTANT: Sorry, no flights found.

USER: Ok, not an issue.

ASSISTANT: Thank you for choosing us.

USER: Thank you for providing information.