You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I provide assistance to you?

USER: I am planning to visit Olympic National Park at Washington, could you please help me with booking a flight ticket from PHL to DCA?

ASSISTANT: Sure, we are glad to help you for booking. Let me know your class preference.

USER: I am looking for a business class ticket.

ASSISTANT: Ok, When you are planning to travel?

USER: I would like to depart on May 5th and return on May 7th.

ASSISTANT: Kindly please share your journey timings.

USER: I am comfortable with any timing.

ASSISTANT: May I know your good name please?

USER: I am Eric Parker.

ASSISTANT: Please wait for some time, I will check the availability of flights and get back to you.

USER: Sure, take your time.

ASSISTANT: Sorry for the inconvenience, there were no flights found based on your specified details.

USER: Ok, not an issue. Anyways, thank you for the information.

ASSISTANT: Thank you for approaching our service.