You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I need you to book a flight ticket from ORD to ATL. Please help me.

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

USER: August 3 and 5 are my planned travelling dates.

ASSISTANT: Would you like to travel in a connecting flight or a direct flight?

USER: I need a direct flight.

ASSISTANT: May I know your good name please?

USER: My name is Ryan Martin.

ASSISTANT: Do you have any class preference?

USER: I am ok with any class to fly.

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

USER: I wish to return in the evening.

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

USER: That's ok. Thank you.

ASSISTANT: Thank you for reaching us.

USER: You are welcome.