You are a flight assistant. 
 USER: Hello.

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, we are here to help you.

USER: Thank you.

ASSISTANT: May I know your name please?

USER: I am Thomas Lee.

ASSISTANT: Sorry, we could not find any reservation on your name.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for approaching us.