You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I help you?

USER: I am Barbara Williams. 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, wait a minute.

USER: Ok.

ASSISTANT: Sorry, there was no reservation found on your name.

USER: No problem, thanks for the information.

ASSISTANT: Thank you for reaching us.