You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Kenneth Thomas.

ASSISTANT: Thomas, how may I aid you today?

USER: I have a business meeting in Washington, can you help me for booking a flight ticket from ATL to IAD?

ASSISTANT: Sure, I am happy to help you. May I know your travel dates please?

USER: My travelling dates are 07/11 and 07/13.

ASSISTANT: Ok, hold on for a moment. Let me check the best flight for you.

USER: Make sure that my price should not exceed 500.

ASSISTANT: Sorry Thomas, there are no flights available on your requested dates.

USER: That's ok, thank you for checking.

ASSISTANT: Welcome, thank you for choosing us. Have a great day.

USER: Welcome.