You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I amend you?

USER: I am Karen Anderson. Owing to an emergency, I want to change my existing reservation.

ASSISTANT: Sure, I can help you best. Please wait a while.

USER: Sure.

ASSISTANT: Sorry, we did not find any reservation with your name.

USER: Not an issue.

ASSISTANT: Thanks for consulting us, have a nice day.

USER: Thanks for your quick response.