You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: My name is Patrick Hall.

ASSISTANT: Yes Hall.

USER: Me and my friends are planning to travel Washington DCA to see the gardens and auditorium, could you book a ticket?

ASSISTANT: Sure Hall. May I know your travelling dates and airport codes of source?

USER: My travelling dates are 10/18 and 10/20 and source region is PHL.

ASSISTANT: Sorry Hall, no flights as per your details.

USER: Ok, no problem. Thank you for information.

ASSISTANT: Thank you for contacting us. You are welcome.