You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you now?

USER: William Thompson here. I want to change my recent reservation due to an emergency will you help me with that?

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

USER: Ok,sure.

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

USER: Thank you for your information.

ASSISTANT: Thank you for reaching us.