You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I help you?

USER: I am planning to visit Denver , will you help me in booking the flight ticket from PHL to DEN?

ASSISTANT: Sure, may I know your travelling dates?

USER: My travelling dates are Aug 18 and Aug 20.

ASSISTANT: Do you have any connection limit?

USER: I need a flight with single connection.

ASSISTANT: Any other preferences?

USER: No, thank you for asking.

ASSISTANT: May I know your name?

USER: Myself Brian Harris.

ASSISTANT: Sorry, there are no flights found with your details.

USER: Ok, not an issue. Thank you for your information.

ASSISTANT: Thank you.