You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I am Brandon Allen, I already book a ticket to New York to meet my brother but due to my bad health my trip is postponed. Can you change my existing reservation?

ASSISTANT: Sure, we are here to help you. Please hold a moment.

USER: Sure.

ASSISTANT: Thank you for holding on, unfortunately no reservation found with provided name.

USER: Thank you for the information.

ASSISTANT: Thank you for approaching us.