You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How best can I aid you today?

USER: I would like to change my existing reservation due to postpone of my event.

ASSISTANT: Sure, I am happy to help you with that. For checking your reservation status, we need to know your name. So, please forward me your name.

USER: Sure, Gary Smith here.

ASSISTANT: Ok, please wait for a moment.

USER: Sure, I will wait for your response.

ASSISTANT: We regret to say that, there is no reservation found on your name in our records.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for choosing us, have a great day ahead.