You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I want to change an existing reservation due to my meeting got preponed. Can you help me out?

ASSISTANT: OK, to check the details please provide me your name?

USER: I am Susan Jones.

ASSISTANT: Sorry to say that there is no reservation with your name.

USER: Ok, no problem. Thanks for the information.

ASSISTANT: Thank you, for reaching us.