You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you?

USER: Owing to emergency, my business conference got postponed. So I want you to change my existing reservation?

ASSISTANT: Sure, may I have your name please?

USER: Sure, Ronald Jones here.

ASSISTANT: Please wait for a while, I will check and revert to you.

USER: Sure.

ASSISTANT: We are sorry to notify, there is no reservation found on your given name.

USER: Ok, no worries at all.

ASSISTANT: Thank you for choosing us.

USER: Thanks for your assistance.