You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you out?

USER: I am Gary Harris. I am planning to visit Denver DEN from Seattle SEA. Can you make a reservation for me?

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

USER: Thank you. my planned trip dates are on Aug 14 and return on Aug 16.

ASSISTANT: Do you have any connection limit?

USER: Yes, I need a single connecting flight.

ASSISTANT: Do you need any preference?

USER: Yes, I want an economy class.

ASSISTANT: Do you prefer any departure and arrival timings?

USER: Yes, I want to depart in the Afternoon time.

ASSISTANT: Sorry, there are no flights found.

USER: Ok, not an problem.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your information.