You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I want to change my reservation due to my bad health, can you help me?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: May I know your name please?

USER: My name is Andrew Johnson.

ASSISTANT: Please hold on a moment.

USER: Ok.

ASSISTANT: Andrew Johnson, no reservation has been found on your name in our database.

USER: Ok, thank you for the information.

ASSISTANT: Thank you for choosing us.