You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Margaret Roberts.

ASSISTANT: How can I assist you?

USER: Can you help me to book a flight ticket from ATL to AUS?

ASSISTANT: Sure, I can help you with that. May I know your travel dates please?

USER: Ok, please can you book for the dates Feb 14 and Feb 16?

ASSISTANT: Sure, in which class do you prefer to travel?

USER: No yet planned any class, please book a ticket for any class available.

ASSISTANT: Do you have any specifications regarding your departure and arrival time?

USER: Yes, I need a return flight for the timing which is during evenig.

ASSISTANT: Ok, please let me know if you have any other specifications.

USER: No.

ASSISTANT: Please wait for a while.

USER: Ok, I will wait.

ASSISTANT: Sorry to inform you that there are no flights available for you on those dates with your given details.

USER: That is ok, thank you for providing the information.

ASSISTANT: Thank you for choosing us, have a nice day.