You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. What assistance do you require from our agency?

USER: I want to attend a Seminar in San Francisco. Can you please help me for booking the flight ticket?

ASSISTANT: Sure, I am happy to help you in ticket booking. Can you please let me know your planned travel dates?

USER: My travelling dates are Sep 12 and Sep 14.

ASSISTANT: Can I know your source and destination airport codes?

USER: My airport codes are LAS and SFO.

ASSISTANT: Is there any airlines preference?

USER: No.

ASSISTANT: Do you prefer a direct flight or a connecting flight?

USER: Connecting flight.

ASSISTANT: Ok, please tell me your good name.

USER: My name is Thomas Miller.

ASSISTANT: Ok, please give me a minute.

USER: Ok, I will wait.

ASSISTANT: Sorry to inform you, there are no flights found in this route.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for opting us.