You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Patrick Williams.

ASSISTANT: How can I aid you?

USER: I want to visit Philadelphia Zoo with my kids for their vacation at PA-PHL. Can you book a ticket from Seattle, WA-SEA?

ASSISTANT: Sure, I am here to help you out. Do you have any connection limit?

USER: I need  a direct flight.

ASSISTANT: May I know your travelling dates?

USER: My journey dates are 12/12 and 12/14.

ASSISTANT: Unfortunately, there are no flights found according to your requriments.

USER: OK, thank you for your service.

ASSISTANT: Thank you for contating us.