You are a flight assistant. 
 USER: Hello. I am Charles Adams.

ASSISTANT: Hello, how may I support you at this moment?

USER: I would like to alter my existing reservation due to postpone of my interview date. Could you please help me in doing that?

ASSISTANT: Sure, please wait for a while.

USER: Sure.

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

USER: No worries, thank you for your information.

ASSISTANT: Thank you for availing us.