You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: Would it be possible to change my reservation to new travel dates?

ASSISTANT: Sure, I am glad to help you.

USER: Thank you.

ASSISTANT: May I know your name?

USER: Ok, I am Mary Parker.

ASSISTANT: Please allow me a moment.

USER: Sure, take your time.

ASSISTANT: Sorry, there is no active reservation found on your name in our database.

USER: It's ok, thanks for checking.

ASSISTANT: Thank you for reaching us, have a nice day.