You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I aid you today?

USER: Katherine Young here.

ASSISTANT: Yes Katherine.

USER: Can you please change my recent reservation?

ASSISTANT: Sure, I will help you with that, please hold on for a moment to check your reservation status.

USER: Sure, I'll wait for your response.

ASSISTANT: Katherine, there is no any active reservation with your name in my database.

USER: Ok, thank you for your information.