You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I assist you?

USER: Owing to an emergency, my meeting with client got postponed, so I want you to change my existing reservation.

ASSISTANT: Sure. Tell me your name please?

USER: Sure, Carolyn Davis here.

ASSISTANT: Please wait.

USER: Sure.

ASSISTANT: Thanks for waiting. But I am sorry to say that there is no flight reservation on your name to change it.

USER: Ok, no issues. Thank you for your assistance.

ASSISTANT: Thank you.