You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I give assistance to you?

USER: Can you please help me with changing my existing reservation due to postpone of my seminar.

ASSISTANT: Sure, we are glad to help you to change it. May I know your name, to check with your previous reservation?

USER: I am Timothy White.

ASSISTANT: Ok, please wait for a couple of minutes.

USER: Sure, I will wait.

ASSISTANT: Thanks for your time, there was no reservation found on your name to change it.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for approaching us.