You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Ryan Walker here.

ASSISTANT: In which way I can aid you today?

USER: I want to travel from Oakland to Las Vegas for attending a Seminar. Can you please help me for booking the flight ticket?

ASSISTANT: Sure, I am happy to aid you in booking flight ticket. Could you please mention your travel dates for booking flight ticket?

USER: My travelling dates are from 08/25 to 08/27.

ASSISTANT: May I know your airport code names for further process?

USER: My airport codes are from OAK to LAS. Make sure my connections limit is 0.

ASSISTANT: Ok, please hold on a moment, I will check flight availability in this route.

USER: Ok, I will wait.

ASSISTANT: Sorry for the inconvenience no direct flights are available in this route as per your requested dates.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for reaching us, have a good day.