You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am Richard Brown, I want to change my reservation as my plan to meet my friend is postponed. Can you change my reservation?

ASSISTANT: Sure, please give me a minute.

USER: Sure.

ASSISTANT: There is no reservation found with your name.

USER: Thank you for the details.

ASSISTANT: Thanks for reaching us.