You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello,. How can I aid you today?

USER: I want to change my existing reservation as our tour got postponed, please help me out.

ASSISTANT: Sure, we are happy to help you. Let me know your name for checking the reservation?

USER: I am Emily Anderson.

ASSISTANT: Wait for a while.

USER: Ok.

ASSISTANT: Thanks for waiting, there is no reservation found on your name to change your existing reservation.

USER: Ok, no problem.

ASSISTANT: Thank you for opting us.

USER: Thank you for the information.