You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I am William Jones. I want to book a flight ticket to surprise my parents on there wedding anniversary. Will you help me in flight booking?

ASSISTANT: Sure, I am here to help you. Can you please provide your airport codes?

USER: My origin from CA - LAX and my destination to CA - SFO.

ASSISTANT: Please provide your travel dates.

USER: My departure is 07/13 and my return date on 07/15.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry, there were no flights found on your dates.

USER: No problem. Thanks for your service.

ASSISTANT: Thank you for choosing us.