You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: I'm Michael Miller. As my health is not good, I want to postpone my planned trip. Can you please change my recent reservation?

ASSISTANT: Sure, please wait for a moment to check your details.

USER: Ok, carry on.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: That's ok, no issues. Thank you for your service.

ASSISTANT: Thank you for choosing us, have a nice day.