You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Can you please help me in booking my flight ticket from DEN to ATL?

ASSISTANT: May I know your desired travel dates please?

USER: My travelling dates are from 09/11 to 09/13.

ASSISTANT: Do you have any specifications?

USER: Yes, I need a direct flight. Also, my return time should be in the evening.

ASSISTANT: There is a no flight on your desired travel dates.

USER: It's ok, thank you.

ASSISTANT: May I know your name please?

USER: Myself Amy Rodriguez.

ASSISTANT: Thank you for opting us.

USER: Welcome.