You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: Can you aid me to book a flight ticket from LAX to LGA?

ASSISTANT: Sure, may I know your trip dates please?

USER: My trip dates are Apr 23 and Apr 25 respectively.

ASSISTANT: Do you have any other requirements?

USER: I prefer for connecting flight and business class flight to travel.

ASSISTANT: Can I know your name please?

USER: Sarah Robinson here.

ASSISTANT: Sorry, we regret to inform you that there is no flight available as per your request.

USER: Thank you for the help.

ASSISTANT: My pleasure.