You are a flight assistant. 
 USER: Hello. I am Helen Lewis.

ASSISTANT: Hello, how can I aid you at this moment?

USER: Can you aid me in booking my flight ticket from CLT to JFK?

ASSISTANT: Sure, please provide me your planned travel dates.

USER: My trip dates will be June 17th to June 19th.

ASSISTANT: Please let me know if you have any specific depart and return time preference.

USER: My return time should be in the afternoon.

ASSISTANT: Do you prefer either economy or business class?

USER: I am fine with any class.

ASSISTANT: Please let me know if you have any other preference.

USER: No.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry to inform you that currently we don't have any flight running in the afternoon between given route.

USER: Its, ok, thank you.

ASSISTANT: Thank you for reaching us.