You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

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

ASSISTANT: May I know your name please?

USER: Thank you. Myself Dennis Turner.

ASSISTANT: No reservation found at the moment as per your request.

USER: Ok, no problem. Anyway thank you for checking out.

ASSISTANT: Thank you for choosing us.