You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: Owing to an emergency, I want to change an existing reservation, so please help me in changing the reservation.

ASSISTANT: Sure, may I know your name?

USER: My name is Shirley Walker.

ASSISTANT: Please give me a moment to check your ticket status.

USER: Ok.

ASSISTANT: Sorry Shirley Walker, no reservation is available by your name.

USER: Not an issue. Thank you.

ASSISTANT: Thank you for reaching us.