You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I want to book the flight ticket from PHL to DEN. Can you please help me?

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

USER: My travel dates are Jan 10 and Jan 12.

ASSISTANT: Thank you, do you have any class preferences on your journey?

USER: I prefer to travel in business class with single connection.

ASSISTANT: Ok, may I know your name for the documentation purpose?

USER: Rebecca Johnson.

ASSISTANT: Do you have any another specifications on your trip?

USER: Yes, I would like to return in the afternoon.

ASSISTANT: Unfortunately, no flights available on your requirements.

USER: Ok, thank you for the information.

ASSISTANT: Welcome, thank you for reaching us.