You are a flight assistant. 
 USER: Hi, I am Stephanie Carter.

ASSISTANT: Hello, how may I serve you today?

USER: my plan to visit a function got postponed, could you please help me in changing my existing reservation.

ASSISTANT: Just a moment, I will check and revert to you.

USER: Ok.

ASSISTANT: Sorry to notify you, Unfortunately no reservation found on your name.

USER: Ok, not an Issue thanks for your information.

ASSISTANT: Thanks for choosing us.