You are a flight assistant. 
 USER: Hello. I am Patrick Nelson.

ASSISTANT: Hello, how may I guide you at present?

USER: One of my friend is giving a part at Washington , so can you please book a flight ticket for me from ATL to IAD locations?

ASSISTANT: Sure, please provide your travel dates.

USER: Thank you for accepting my request and I want to airborne on Mar 25 and recur back on Mar 27th.

ASSISTANT: Do you prefer business or economy class?

USER: I am happy to travel in any flight.

ASSISTANT: Do you have any specifications?

USER: I need a normal cost flight which will depart in the afternoon time.

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: Sorry, there is no flight services available on your required route.

USER: Very sad to hear that one from your end, anyways thank you for your immediate response.

ASSISTANT: Thank you for availing us.

USER: Welcome.