You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello.

USER: I am Raymond Brown.

ASSISTANT: How can I help you right now?

USER: Can you please change my existing reservation, due to en emergency?

ASSISTANT: Sure, please wait for a moment to check it. Thank you for waiting.

USER: Sure. Ok.

ASSISTANT: I have checked based on your request in our booking portal but it is showing that there is no reservation found for the user name to change it.

USER: Ok, no issue. Thank you.

ASSISTANT: You are most welcome and have a nice day.