You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: David Clark here. I need a direct flight from ATL to IAD.

ASSISTANT: Please share your planned dates of trip.

USER: My travel dates are 05/09 and 05/11.

ASSISTANT: Sorry David, no flight is found on your route.

USER: It's ok, thank you.

ASSISTANT: You are welcome.