You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you for today?

USER: I need to book a flight ticket with the name Alexander White, can you book me a ticket with price under 500?

ASSISTANT: Sure, would you please provide your dates of travel?

USER: Ok, my preferred dates are 08/08 and 08/10.

ASSISTANT: Ok, please mention your city codes.

USER: I would like to travel from Oakland, CA-OAK as I need to attend a seminar which is held at Austin, TX-AUS.

ASSISTANT: Sorry to say, there are no flights found on your dates.

USER: Thank you for the information.

ASSISTANT: Thanks for reaching us, have a good day.