You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I oblige you today?

USER: I would like to change my reservation as my exams postponed to some other dates, can you please help me out with that?

ASSISTANT: Sure, may I know your good name?

USER: Myself Susan Harris.

ASSISTANT: Please hold a moment.

USER: Sure.

ASSISTANT: Thank you for waiting, there is no active reservation found with the given name.

USER: Ok, no problem. Anyway thank you for checking out.

ASSISTANT: Thank you.