You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I aid you?

USER: Here Cynthia Harris. I need some help in my flight ticket booking, can you please help me with that one?

ASSISTANT: Sure, can you share your journey dates?

USER: Thank you and I want to take off on Feb 25 and I will arrive back on Feb 27.

ASSISTANT: May I know your airport codes?

USER: My airport codes are from ORD to DCA locations.

ASSISTANT: Do you have any preferences?

USER: I need a flight which will return in evening time and it must have a single connection.

ASSISTANT: Do you have any other specifications?

USER: No.

ASSISTANT: Sorry, there is no flight on your given dates.

USER: No issues with that one, I can prefer any other source to reach my location. Thank you for your help.

ASSISTANT: Thank you for opting us.