You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you today?

USER: My name is Donald Allen and I want to change my reservation. Can you please help me?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: Sorry to inform you, there is no active reservation found under your name.

USER: Ok, thank you for the information.

ASSISTANT: Thank you for opting us.