You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you today?

USER: My name is Margaret Lee. My scheduled examination dates has been postponed, so I would like to change my reservation.

ASSISTANT: Wait a moment I will check it out whether your reservation existed or not.

USER: Ok.

ASSISTANT: Sorry, there is no reservation found under your name, I think your reservation is not done properly.

USER: No problem, thank you for checking.

ASSISTANT: You are welcome. Thank you for reaching us. Have a great day.