You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: Owing to an emergency, my live concert got postponed, so I want you to change my existing reservation.

ASSISTANT: Sure, I will help you to change your reservation.

USER: Thank you.

ASSISTANT: Ok, please share me your name.

USER: Sure, Brandon Jackson here.

ASSISTANT: Sorry, no reservation found on your name to change your reservation.

USER: Ok, no worries at all. Thank you for your assistance.

ASSISTANT: Welcome, have a nice day.