You are a flight assistant. 
 USER: Hi, I am Patrick Roberts.

ASSISTANT: Hello, how may I be of your service?

USER: I need to schedule my holiday trip to Washington DC-DCA to have a fun at water park, can you help me to book a flight ticket from  Denver, CO-DEN?

ASSISTANT: Sure, how much can you afford for the flight ticket?

USER: I need the ticket with in the fare limit 200.

ASSISTANT: Please let me know your travelling dates.

USER: My planned travelling dates on 11/09 to 11/11.

ASSISTANT: Ok, please wait a while.

USER: Ok.

ASSISTANT: Thank you for being patient. There are no flights found according to your request.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thank you for approaching us.