You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am Larry Adams. I am planning to visit Olympic National Park at Washington, could you please help me with booking a flight ticket from BOS to IAD?

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

USER: I would like to depart on Apr 17th and return on Apr 19th.

ASSISTANT: Please wait for a while.

USER: I need a flight ticket in business class. Make sure that my airline is from normal cost.

ASSISTANT: Sorry, there is no flight available as per your request.

USER: That's ok, not an issue. Anyways, thank you for the information.

ASSISTANT: Most welcome.