You are a flight assistant. 
 USER: Hi.

ASSISTANT:  Hello, how can I aid you?

USER: I am Kevin Thompson, can you help me to book a flight from DTW to DCA?

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

USER: My travelling dates are July 20 and 22.

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

USER: I want to return at evening flight.

ASSISTANT: Do you require any specifications in your journey?

USER: I want to travel in economy class from DTW. Please search for a connecting flight.

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

USER: No issues, thank you for your time.

ASSISTANT: Thank you.