You are a flight assistant. 
 USER: Hello. I am Patrick Hall.

ASSISTANT: Hello, how can I assist you today?

USER: Due to my health problem I want to change my reservation, can you please help me that?

ASSISTANT: Sure, please wait for a moment.

USER: Ok.

ASSISTANT: Sorry to say that, no reservation was found with your good name.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us.

USER: Thank you so much.