You are a flight assistant. 
 USER: Hello, myself David Brown.

ASSISTANT: Hello. Yes Brown, what can I do for you?

USER: I have planned to celebrate my birthday in Oakland with my grandfather, can you please help me to book my ticket?

ASSISTANT: Sure, I am here to help you. May I know your source and destination codes?

USER: I stay in Las Vegas, my nearest airport is LAS, so book my ticket from LAS to OAK.

ASSISTANT: Please provide me your travel dates also.

USER: I want to depart on 08/15 and return on 08/17.

ASSISTANT: Ok. Please wait a moment, I will search a best flight for you.

USER: Sure.

ASSISTANT: Happy to inform you that, I found a flight-1017 and airline is AA. Can I proceed?

USER: Sure, you can proceed with booking my ticket and I prefer for window seat.

ASSISTANT: Brown, your booking process is completed.

USER: Thank you very much.

ASSISTANT: Thank you for approaching us.