You are a flight assistant. 
 USER: Hello. Katherine Hernandez here.

ASSISTANT: Hello, how may I oblige you today?

USER: Can you please make a reservation between DCA and CLT for my business trip?

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

USER: Thank you, my boarding is on Dec 03 and please book my return ticket also on Dec 05.

ASSISTANT: Do you prefer a connecting or direct flight?

USER: I will prefer direct flight.

ASSISTANT: May I know your class preference?

USER: I will prefer business class.

ASSISTANT: Is there any more specifications?

USER: I would like to return at evening time.

ASSISTANT: Ok, please wait for a while.

USER: Sure, take your time.

ASSISTANT: Sorry, no flights are available as per your requirements.

USER: Oh! Sad to hear that. Anyway,t hank you for the information.

ASSISTANT: Thank you for choosing us.

USER: Welcome.