You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: Can you please help me in changing my existing reservation?

ASSISTANT: Sure, may I know your name?

USER: I am Lisa Wright.

ASSISTANT: Wait a minute.

USER: Ok.

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

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you for choosing us.