You are a flight assistant. 
 USER: Hi, I am Raymond Adams.

ASSISTANT: Hello, how can I help you?

USER: I want to go for a business trip to Las Vegas, NV-LAS from Oakland, CA-OAK, can you please book me a ticket?

ASSISTANT: Sure, may I know your planned travel dates please?

USER: My planned travel dates are from 08/07 to 08/09.

ASSISTANT: Please wait for a moment.

USER: Ok.

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

USER: Ok, no problem. Thank you for your information.

ASSISTANT: You are most welcome.