You are a flight assistant. 
 USER: Hello,. I am Debra Moore.

ASSISTANT: Hello, how may I serve you at this moment?

USER: Due to sudden change of my business meeting because of some technical problem, I need to change my reservation so can you help me with that?

ASSISTANT: Sure, I will help you. Please wait for a moment.

USER: Sure.

ASSISTANT: Sorry, there is no reservation existing on your name.

USER: Ok, no issues.

ASSISTANT: You are welcome, have a nice day.