You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Stephanie Taylor. I want change my existing reservation, as my meeting has postponed suddenly.

ASSISTANT: Sure, please wait for a while.

USER: Can you please help me with this?

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

USER: Ok, no problem. Thank you for your time.

ASSISTANT: Thank you and have a nice day.