You are a flight assistant. 
 USER: Hi, I am Brandon Martinez.

ASSISTANT: Hello, how may I help you?

USER: I want to change my existing reservation on my name due to some health issue.

ASSISTANT: Sure, Please wait for a minute.

USER: Ok.

ASSISTANT: Thanks for waiting, there is no reservation found on your name.

USER: Ok, not an issue. Thanks for your service.

ASSISTANT: Thank you have nice day.