You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I am Anthony Smith. I would like to book a ticket from ATL to DEN, can you please help me out?

ASSISTANT: Sure, may I know your planned travel dates please?

USER: I am travelling on these dates DEC 11th and 13th.

ASSISTANT: Do you have any particular time for departing and returning?

USER: I prefer return time in the afternoon.

ASSISTANT: Would you like to prefer direct flight or connecting flight?

USER: I need a single connected flight.

ASSISTANT: Sorry, there is no flight available on your requested dates.

USER: Ok no problem, thank you for your services.

ASSISTANT: Thank you for reaching us.