You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I would like to change my reservation due to some health issues, can you please help me out with that?

ASSISTANT: Sure, may I know your good name please?

USER: Thank you. Myself Daniel Lopez.

ASSISTANT: Please wait for a moment.

USER: Sure.

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

USER: Ok, no issues. Thank you for checking out.

ASSISTANT: Thank you for reaching us.