You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you?

USER: I would like to prefer business class for my journey from IAD to DFW. Please help me in booking a ticket.

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

USER: My planned travel dates are on Jan 31 and Feb 02.

ASSISTANT: Do you have any specifications?

USER: I would like to return in the evening and I need a connecting flight.

ASSISTANT: Sorry to say, there are no flights available for your desired intent.

USER: Ok, no issues. Thank you for your information.

ASSISTANT: Please provide me the name.

USER: My name is Joseph Clark.

ASSISTANT: Thank you for reaching us.