You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: I am Ashley Wilson. I want to change my existing change reservation, due to some health issue. Can you please help me?

ASSISTANT: Sure, please give me a moment to check your details.

USER: Ok, take your time.

ASSISTANT: Sorry, no reservation found on your name.

USER: It's ok, thank you for your information.

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