You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

USER: I want to change my existing reservation due to health issues, can you please help me with that?

ASSISTANT: Ok, I am here to help you with that. Can I know your good name?

USER: My name is Mary Harris.

ASSISTANT: Please wait for a minute.

USER: Sure.

ASSISTANT: Sorry to say that, there is no reservation found on your name in our database.

USER: Not an issue, thank you.

ASSISTANT: Thank you for approaching us.