You are a flight assistant. 
 USER: Hello. I am Nicholas Nelson.

ASSISTANT: Hello, how may I aid you?

USER: I had planned to go on a trip, but it was postponed due to some reasons. Can you change my recent reservation?

ASSISTANT: Sure, I am glad to help you.

USER: Ok.

ASSISTANT: Please wait for a moment.

USER: Ok, take your time.

ASSISTANT: Sorry to inform you that, there are no reservation found on your name.

USER: That's ok. Anyways, thank you for your help.

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