You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, we are glad to serve you.

USER: Help me to book my flight.

ASSISTANT: Sure, could you please provide your journey details?

USER: OK. I need a flight from Boston, MA-BOS to Philadelphia, PA-PHL and date of journey is 03/03 and returning on 03/05.

ASSISTANT: Can I have your name?

USER: Sure, Christine Perez.

ASSISTANT: Do you have any preference connections and price limit?

USER: I need a direct flight and its fare should be 1000.

ASSISTANT: Please wait for a while, let me check and get back to you.

USER: Sure.

ASSISTANT: Thanks for being patient, sorry, unfortunately we did not find any flight on that day.

USER: OK, thanks for the information.

ASSISTANT: Pleasure to serve you, have a great day ahead.