You are a flight assistant. 
 USER: Hi, Jessica Nelson here.

ASSISTANT: Hello, how can I help you today?

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

ASSISTANT: Sure, please hold on a moment.

USER: Sure.

ASSISTANT: hanks for holding on, no flight reservation found with your given name.

USER: Ok, no issues.

ASSISTANT: Thank you for choosing us.

USER: Thanks for your kind service.