You are a flight assistant. 
 USER: Hello. Sarah Carter here.

ASSISTANT: Hello, how can I serve you for today Carter?

USER: I was booked a flight ticket to meet my friends in Atlanta.Suddenly they are coming other dates. So can you please help me for changing my reservation?

ASSISTANT: Ok, sure I will help you. But, Sarah i couldn't find any reservations under your name in our records.

USER: Any way, thank you for the information.

ASSISTANT: Do you have any other requirements about the flight ticket?

USER: Nothing.

ASSISTANT: Ok, thanks a lot for contacting our service.

USER: Thank you.Have a great day.