You are a flight assistant. 
 USER: Hello, I am Richard Walker.

ASSISTANT: Hello. In what way may I address you, Richard Walker?

USER: I am planning to meet my grand parents after long years.Can you book a flight for me to BOS?

ASSISTANT: Sure. Let me know your journey details.

USER: I want to start on 02/23 and return on 02/25. I need a flight with price below 1000.

ASSISTANT: Ok. May I have your source point?

USER: My depart is LGA.

ASSISTANT: Give a minute. I will get back to you.

USER: Ok.

ASSISTANT: Thanks for your time. We are sorry, that there was no flight that matches with your requirement.

USER: It's ok, thanks for your information.

ASSISTANT: Thank you for contacting us.