You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I want to change my previous reservation, due to some health issues I am unable to travel those dates, can you please change my reservation?

ASSISTANT: Yes, I can help you with that. Can I know your name for checking?

USER: Thanks. Sure, my name is Jason Young.

ASSISTANT: Ok, give me a moment.

USER: Ok.

ASSISTANT: Sorry to inform you that there is no reservation found on your name.

USER: Oh! It's ok no problem. Thank you for your information.

ASSISTANT: Thank you for reaching us.