You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

USER: I am Margaret Green. I want to change my reservation, can you help me?

ASSISTANT: Sure, I am here to help you. Please, wait.

USER: Sure.

ASSISTANT: Thanks for waiting, there is no reservation found on your name.

USER: Thank you.

ASSISTANT: Thank you for opting us.