You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello.

USER: I am Patrick Evans.

ASSISTANT: How can I help you now?

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

ASSISTANT: Ok. Sorry, there was no reservation on your name to change.

USER: Ok, not an issue. Thank you for your information.

ASSISTANT: Thank you for picking us.