You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello.

USER: I am Samuel Evans.

ASSISTANT: Samuel Evans, how can I assist you?

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

ASSISTANT: Sure, please standby I have to check the reservation list.

USER: Sure.

ASSISTANT: There was no reservation on your name to change.

USER: Ok, no issue. Thank you.

ASSISTANT: Thank you for availing us. Have a nice day.