You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: I want to change my reservation as my plan to meet my share holder is postponed. Can you aid me to change it?

ASSISTANT: Sure, may I know your name?

USER: Sure, my name is Helen Carter.

ASSISTANT: Wait a minute.

USER: Sure.

ASSISTANT: There was no reservation found on your name in our database base.

USER: That's Ok, thanks for your response.

ASSISTANT: Thank you for reaching us.