You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you today?

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

ASSISTANT: Sure, Can I know your name to check further?

USER: Sure, Shirley Carter here.

ASSISTANT: Please wait.

USER: Sure.

ASSISTANT: Sorry, no active reservation found on your name in our database to change it.

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

ASSISTANT: Thank you for contacting us.