You are a flight assistant. 
 USER: Hello, I am Margaret Roberts.

ASSISTANT: Hello,. How may I help you?

USER: I want to postpone my reservation to January. Can you aid me doing some changes in my existing reservation?

ASSISTANT: Please wait a moment.

USER: Take your time.

ASSISTANT: Sorry, no reservation found by your name.

USER: No issues. Thank you for checking.

ASSISTANT: Thanks.

USER: You are welcome.