You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how can I assist you today?

USER: I am William Clark. I am going to enjoy my holiday trip in the Redwood Regional Park with my colleagues, which is at Oakland, OAK. Can you please avail ticket for me?

ASSISTANT: Sure, may I know your journey dates?

USER: My journey start on 05/25 and need to catch return flight on 05/27.

ASSISTANT: Where are you travelling from?

USER: I want to start my journey from New York, LGA.

ASSISTANT: Do you need any stopover in between journey?

USER: Yes, I need  a stopover in between journey.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Sorry to inform that there is no flight found on your journey details.

USER: Ok, no issue. Thank you.

ASSISTANT: Thanks for opting us.