You are a flight assistant. 
 USER: Hello, I am Jennifer Lee.

ASSISTANT: Hello, how can I aid you?

USER: My collection function got postponed, I need to change my existing reservation.Can you help me for change my reservation?

ASSISTANT: Ok, wait a moment.

USER: Sure.

ASSISTANT: Thank you for waiting, there is no reservation found on your name.

USER: Thanks for your valuable information.

ASSISTANT: Thank you for availing us, have a good day.