You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Can you help me to book a flight ticket from DFW to JFK?

ASSISTANT: Sure, we are glad to help you. Can you please let me know your travelling dates?

USER: My travel dates are Aug 21 and Aug 23.

ASSISTANT: Do you prefer any lay by in between journey?

USER: Yes, I prefer lay by in between my journey.

ASSISTANT: Is there any other specifications for you?

USER: I would like to prefer return back in the morning time.

ASSISTANT: May I know your good name?

USER: I am Karen Johnson.

ASSISTANT: Sorry, no flights are available on your journey dates.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for opting us.