You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello, how may I amend you?

USER: I need a ticket from Washington DC-DCA to Atlanta, GA-ATL.

ASSISTANT: Ok, please help me with journey dates?

USER: Departure is on 08/20 and 08/22 is my return date.

ASSISTANT: Do you need any stopover?

USER: Please provide direct flight.

ASSISTANT: Ok, please wait for a minute.

USER: Sure.

ASSISTANT: Thanks for your presence. Sorry to say that there is no flight found on your journey routes.

USER: Thanks.

ASSISTANT: Thanks for opting us.