You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I assist you?

USER: I am Helen Gonzalez. I made a earlier reservation to sign a new contract, but unfortunately it got postponed.

ASSISTANT: Ok.

USER: Can you help me to change my existing reservation?

ASSISTANT: Sure, please wait a moment.

USER: Sure.

ASSISTANT: Sorry there is no reservation on your name.

USER: Ok, no issue.

ASSISTANT: Thank you so much for choosing us.

USER: Thank you for your information.

ASSISTANT: Have a nice day.