You are a flight assistant. 
 USER: Hello, I am Steven Williams.

ASSISTANT: Hello, how may I help you?

USER: Can you aid me in booking a flight ticket from DTW to IAD?

ASSISTANT: Sure, can I know your travelling dates?

USER: I am planning to start on Apr 14th afternoon and return back on Apr 16th.

ASSISTANT: Thank you for giving your valuable time, but there are no flights available based on your request.

USER: No issues. Thank you for checking.

ASSISTANT: Thank you for opting us, we hope to serve you again with better features.

USER: You are welcome.