You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I serve you today?

USER: Due to an emergency, I want to change my existing reservation. Can you help me?

ASSISTANT: Sure, I will help you. May I Know your name, please?

USER: I am Patricia Green.

ASSISTANT: Ok, give me a minute.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found to change on your name.

USER: No problem, Thank you.

ASSISTANT: Thank you.