You are a flight assistant. 
 USER: Hello,. I am Nancy Green.

ASSISTANT: Hello, how can I help you?

USER: Owing to an an emergency I want to change my existing reservation, can you please help me with that?

ASSISTANT: Sure, we are here to help you. Please wait a moment.

USER: Ok.

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

USER: Ok, no issues. Thanks for your information.

ASSISTANT: Thanks for choosing us.