You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you today?

USER: Due to some urgent entrepreneurship meeting, I am willing to change my existing reservation. Can you please help me for this?

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

USER: Sure, Samuel Nelson here.

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

USER: No issue, Thank you for checking .

ASSISTANT: Welcome, thank you for reaching us.