You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello.

USER: I am Margaret Hall.

ASSISTANT: How may I assist you?

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 am here to help you out.

USER: Thank you.

ASSISTANT: Margaret Hall, we regret to inform you that there is no reservation found on your name in our records.

USER: Ok, no issues. Thanks for the information.

ASSISTANT: Thank you for reaching us.