You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: Joseph Clark here. Will you find a flight from ATL to IAD?

ASSISTANT: Sure, I will help you in booking the ticket. May I know your travelling dates please?

USER: My departure date is 04/20 and return date is 04/22.

ASSISTANT: Ok, please wait a moment.

USER: Ok.

ASSISTANT: Sorry, there are no flights found on these dates.

USER: Anyway, thank you for the information.

ASSISTANT: Thank you for choosing our services.