You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: I would like to make a flight ticket reservation from ATL to JFK, can you please help me?

ASSISTANT: Please let me know your travelling dates?

USER: Sure, my planned travelling dates are Aug, 19 and 21 respectively.

ASSISTANT: Do you have any class preference?

USER: I am comfortable to travel in any class.

ASSISTANT: Is there any other requirement?

USER: Flight has to be with single connection.

ASSISTANT: May I know your name?

USER: Sure, my name is Alexander Nelson here.

ASSISTANT: Sorry currently there are no flights for your travelling dates. Thank you.

USER: Ok, not an issue.Thank you for your information.