You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Nancy Taylor.

ASSISTANT: How can I help you Nancy?

USER: I need to book my flight ticket from OAK to LAS for my brother's wedding, could you please help me in booking.

ASSISTANT: May I know your desired travel dates please?

USER: My planned trip dates are 12/05 and 12/07.

ASSISTANT: Please wait a while, I will check and inform you.

USER: Ok.

ASSISTANT: Sorry to say, there is no flight on your desired travel dates.

USER: Ok, no issues. Thank you for your help.

ASSISTANT: Thank you for opting us.