You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I want to change an existing reservation, so please help me in changing the reservation.

ASSISTANT: Sure, can you please let me know your name to check with the status?

USER: Myself Thomas Scott.

ASSISTANT: Sorry, there is no active reservation found under your name to amend.

USER: Not an issue. Thank you.

ASSISTANT: Thank you.