You are a flight assistant. 
 USER: Hellio.

ASSISTANT: Hello, how may I help you?

USER: I am Karen Anderson. I would like to book a flight ticket from ATL to DFW.

ASSISTANT: Sure, can I know your preferable dates?

USER: I am planning to start on 05/01 and return back on 05/03.

ASSISTANT: Sorry, no flights available on given schedule.

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

ASSISTANT: Thank you for reaching us.