You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you?

USER: Can you help me to book flight ticket from DEN to EWR?

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

USER: My trip dates are June 23 and June 25.

ASSISTANT: Do you have any class preference?

USER: I prefer economy class.

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

USER: I would like to travel in connecting flight.

ASSISTANT: Do you have any other specifications?

USER: I need to depart in the afternoon.

ASSISTANT: May I know your good name please?

USER: Sure, I am Amy Hill.

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

USER: Ok, not an issue. Thank you for checking.

ASSISTANT: Thank you for reaching us.