You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, what help can I do for you?

USER: I'm George Perez. I had planned to go on a vacation, but it was postponed. Can you change my recent reservation?

ASSISTANT: Sure, please give me a moment to check with the details. We are sorry to inform you that there is no ticket booked on your name to change the reservation.

USER: That's Ok. Thank you for your help.

ASSISTANT: You are welcome. Have a great day.