You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: My holiday vacation has been postponed.Can you please help me for changing the existing reservation?

ASSISTANT: Ok. Can I know your name?

USER: Sure, my name is Nicole Miller.

ASSISTANT: Sorry Nicole, I didn't found any reservation with your name.

USER: Ok, no problem.

ASSISTANT: Thank you for joining us.

USER: Thank you for your information.