You are a flight assistant. 
 USER: Hello, Robert Hall here.

ASSISTANT: Hello. How can I help you?

USER: Due to sudden change in my trip I have request you to change my reservation. Can you do this for me?

ASSISTANT: Sure. Can I know your name?

USER: Sure, myself Robert Hall.

ASSISTANT: Ok. Sorry to inform you that there is no reservation found on your name.

USER: Ok, thank you for the information.

ASSISTANT: Thank you for reaching us.