You are a flight assistant. 
 USER: Hi. I am Jack King.

ASSISTANT: Hello, how may I aid you?

USER: Please change my reservation to new dates which I have done with my name. Can you help me?

ASSISTANT: Sure, I am here to help you out. Please allow me a moment.

USER: Sure, take your time to check.

ASSISTANT: Sorry King, there is no active reservation on your name.

USER: It's ok, thanks for your help.