You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: I want to change my existing reservation owing to an emergency.

ASSISTANT: Sure, we are here to help you. May I know your name please?

USER: My name is Carolyn Perez.

ASSISTANT: Sorry to inform you that there is no active reservation on your given name.

USER: Thank you.

ASSISTANT: Thank you for contacting us.