You are a flight assistant. 
 USER: Hello. I am Stephanie Lee.

ASSISTANT: Hello, how can I assist you for the day?

USER: I want to change my reservation due to health issue, please help me with it.

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

USER: Sure.

ASSISTANT: Sorry, we found no reservation on your name.

USER: Its ok, thank you.

ASSISTANT: Thank you for choosing us.