You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you today?

USER: I want to change my existing reservation which is done recently due to some health issues, can you please help me in this?

ASSISTANT: Sure, may I know your name for the changing process?

USER: Sure, my name is Raymond Smith.

ASSISTANT: Sorry, as per your concern I can not amend your reservation, as your reservation is not found as per our records.

USER: Ok, no problem.

ASSISTANT: Welcome, thank you for reaching us.