You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: This is Richard Scott, can you help me to book a flight ticket from DTW to IAD?

ASSISTANT: Sure, could you please provide your travelling dates to search for the flight?

USER: I am travelling from Sept 14 to Sept 16.

ASSISTANT: Please wait for a moment.

USER: Sure.

ASSISTANT: Sorry to say, no flight is available for you.

USER: That's ok, no issues.

ASSISTANT: Thank you for reaching us, have a nice day.

USER: Thank you for the information.