You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

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

ASSISTANT: Sure, let me know your name please?

USER: Ok, I am James Roberts.

ASSISTANT: Please wait for a while.

USER: Take your time.

ASSISTANT: Sorry to inform you that there is no active reservation on your given name.

USER: It's ok, thanks for checking.

ASSISTANT: Thank you for contacting us.