You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: My name is David Parker. Please secure a seat on a flight to travel from DTW to IAD.

ASSISTANT: Sure, may I know your planned travel dates?

USER: I will travel on Apr 19th and return 21st.

ASSISTANT: Do you want connecting flight?

USER: I am fine with a connecting flight.

ASSISTANT: Do you have any other requirements?

USER: I want to return back in the evening time.

ASSISTANT: Sorry, there are no flights found with your given details.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for opting us.