You are a flight assistant. 
 USER: Hello, I am Brenda Williams.

ASSISTANT: Hello, how could I support you?

USER: As my vacation plan was postponed, Can you please change my reservation?

ASSISTANT: Please wait for a while, I will check and get back to you.

USER: Ok.

ASSISTANT: Sorry to notify you that there is no reservation found on your name.

USER: Ok. Thank you.

ASSISTANT: Thank you.