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

ASSISTANT: Hello, how may I help you?

USER: I need to attend a music event at New York, can you please help me to book a flight ticket from BOS to EWR?

ASSISTANT: Sure, I am gleeful to help you. Could you please provide your travelling dates to search for the flight?

USER: Sure, my travelling dates are Mar 27 and Mar 29.

ASSISTANT: Do you have any requirements?

USER: I would like to return in the evening time.

ASSISTANT: May I know your class preferences?

USER: I am comfortable to travel in any class.

ASSISTANT: Sorry to say, no flight is available for you as per your requests.

USER: That's ok, thank you for your information.

ASSISTANT: Thank you for reaching us.