You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I want to travel from IAD to DFW. Can you help me to book a flight ticket?

ASSISTANT: Sure, I will help you. May I know your planned journey dates please?

USER: I want to travel in the flight on Dec 05 and Dec 07.

ASSISTANT: May I know your name please?

USER: Jacob Mitchell.

ASSISTANT: Do you need a connecting flight?

USER: I want to have a connection of 1.

ASSISTANT: Do you have any other specifications?

USER: I prefer to travel in business class.

ASSISTANT: Jacob Mitchell, no flights has been found on your planned travel dates.

USER: That's ok. Anyways, thank you.

ASSISTANT: Thank you for approaching us.