You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you for today?

USER: I am Kathleen Taylor. I need to book a ticket to meet my parents on 03/15 and It is a round trip OAK. Could you please help me in booking a ticket with fare of 500?

ASSISTANT: Can you please share your return date?

USER: I intend to return on 03/17.

ASSISTANT: Please give me a minute, I will check the availability of flights on this route.

USER: Sure.

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

USER: No problem, thank you for your valuable information.

ASSISTANT: Thank you for contacting us, have a nice day.