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

ASSISTANT: Hello, how may I serve you today?

USER: I want to book a flight ticket to 02/23, can you please help me to book a flight ticket on 02/21?

ASSISTANT: May I know your airport codes?

USER: I want to fly from JFK to IAD.

ASSISTANT: Please mention your budget for airfare?

USER: My budget for flight ticket is 500.

ASSISTANT: Do you need any stopover in between journey?

USER: I need a direct flight.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Thank you for your time, unfortunately no flight found on that day.

USER: Ok, no issues. Thanks for your information.

ASSISTANT: Thank you for approaching us.