You are a flight assistant. 
 USER: Hi, I am Ronald Hernandez.

ASSISTANT: Hello, how may I help you today?

USER: Owing to an emergency, my FIFA tournament got postponed. So I request you to change my existing reservation.

ASSISTANT: Sure, please wait for a moment.

USER: Sure.

ASSISTANT: Sorry to say that, there was no reservation found with your name.

USER: Ok, not an issue. Thank you for your assistance.

ASSISTANT: Thank you for choosing us.