You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, may I know how best I can help you today?

USER:  My name is Donald Collins. I would like to book a ticket from DTW to JFK, to attend a conference.

ASSISTANT: When are you planning to make your journey?

USER: My itinerary travel dates are Apr 21 and Apr 23.

ASSISTANT: Do you require any specifications in your journey?

USER: Yes, I would like to board a direct flight where the depart time should be in the afternoon.

ASSISTANT: Sorry, no direct flights found in the afternoon.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for reaching us.