You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you out?

USER: I am William Hall. Can you help me in booking a flight ticket from DCA to DEN?

ASSISTANT: Sure, I will help you in booking the ticket. May I know your travelling dates please?

USER: I want to travel on 11/14, and return on 11/16.

ASSISTANT: Do you need any specifications?

USER: I need to return in the morning time.

ASSISTANT: Can I know your preferences?

USER: I prefer a business class.

ASSISTANT: Do you need any connection limit?

USER: I need a connecting flight.

ASSISTANT: Sorry, there are no flights found.

USER: Ok, no issues.

ASSISTANT: Thank you for reaching us.

USER: Thanks for the information.