You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I want to book a flight ticket from OAK to LAS. Can you find a flight ticket for me?

ASSISTANT: Sure, can you share me your trip dates?

USER: Ok, my planned trip dates are on May 17 and return on May 19.

ASSISTANT: Do you have any specifications?

USER: I want in the depart in the afternoon time.

ASSISTANT: Can I know your good name?

USER: Ok, I am Gregory Jones.

ASSISTANT: Sorry, no flights are available in this route as per your requested dates.

USER: Ok, not a problem. Thank you for your help.

ASSISTANT: Thank you for reaching us.