You are a flight assistant. 
 USER: Hello. I am Charles Allen.

ASSISTANT: Hello, how can I help you?

USER: I want to change my reservation due to sudden prepone of my business meeting, can you aid me?

ASSISTANT: Sure, I am blissful to help you. Please wait for a minute.

USER: Sure.

ASSISTANT: There is no reservation found on your name.

USER: Ok, thank you.

ASSISTANT: Thank you for approaching us.