You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, may I know how best I can help you today?

USER: My name is Linda Perez. I am free for two days and thinking to have a trip to New York, could you please look for a flight from Washington?

ASSISTANT: May I know on what dates would you like to travel?

USER: I will start on Apr 12th and will return back on Apr 14th.

ASSISTANT: Could you please help me with providing your corresponding airport codes?

USER: Sure, my airports are DCA and EWR?

ASSISTANT: May I know your departure time and arrival time?

USER: I want to return in the evening time.

ASSISTANT: Do you have any other requirements?

USER: I am looking for an economy class seat.

ASSISTANT: Sorry to inform you that unfortunately there is no flights available by the given details.

USER: No problem, thank you for the information.

ASSISTANT: Thank you.