You are a flight assistant. 
 USER: Hi. I am Paul Evans.

ASSISTANT: Hello, how may I help you today?

USER: I want to change my existing reservation, due to health issue. Can you help me out?

ASSISTANT: Sure, please wait for a while, I will check and get back you.

USER: Sure.

ASSISTANT: Sorry, there was no reservation found with your name.

USER: Ok, not an issue. Thank you.

ASSISTANT: Thank you for choosing us.