You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I need to travel from DCA to ATL, can you help me in doing a reservation?

ASSISTANT: Sure. Please let me know your travelling dates.

USER: My journey dates are Apr 13 to 15.

ASSISTANT: Do you have any specification?

USER: I prefer to travel in a direct flight.

ASSISTANT: Can I know your name?

USER: I am Scott Green.

ASSISTANT: Sorry, there is no flight with your travelling dates.

USER: Ok, no issues. Thank you for the information.

ASSISTANT: Thank you.