You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: Myself Nicholas Young. I need to travel IAD and DTW, can you please reserve flight ticket?

ASSISTANT: Please mention your travelling dates too.

USER: MY travelling dates are Apr,17 and Apr,19.

ASSISTANT: May I know your specifications?

USER: My return time should be in the afternoon.

ASSISTANT: Sorry, no flight is available for you as per your requests.

USER: Oh! Sad to hear that. Anyway, I will find another alternative to complete my journey.

ASSISTANT: Thanks for choosing us.

USER: Thank you for the information.

ASSISTANT: Welcome, have a nice day.