You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I made an earlier reservation to attend a marriage, due to some issues it got postponed. Can you please change my reservation?

ASSISTANT: Sure, may I know your name?

USER: My name is Michael Collins.

ASSISTANT: Please wait a moment.

USER: Sure.

ASSISTANT: Sorry, there are no active reservations on your name to change.

USER: Ok, no issue. Thank you.

ASSISTANT: Thank you for reaching our service.