You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: My name is Ryan Martin. I want to book a flight ticket with a price limit of 1000 to celebrate Beer festivals in Philadelphia.

ASSISTANT: Ok, Please let me know your travel dates.

USER: My departure day is 11/14, return day is 11/16.

ASSISTANT: Could you please provide me your journey points?

USER: My source and destination airport codes are DC-DCA, PA-PHL. I want direct flight.

ASSISTANT: Sorry for the inconvenience, there are no flights found on your requested dates.

USER: No problem, thanks for your service.

ASSISTANT: Thanks for choosing our service.