You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: Can you aid me to book a flight ticket from DEN to IAD?

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

USER: My trip dates are Sep 16 and Sep 18 respectively.

ASSISTANT: Would you like to travel in a connecting flight or a direct flight?

USER: I prefer for a connecting flight.

ASSISTANT: May I know your good name please?

USER: Jacob Thomas here.

ASSISTANT: Sorry, there is no flight available on your requested dates.

USER: Thank you for the help.

ASSISTANT: Thank you for reaching us.