You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you today?

USER: I have to change my existing reservation, can you please help me?

ASSISTANT: Sure, we are perky to help you.

USER: Thank you.

ASSISTANT: May I know your good name?

USER: Sure, my name is Stephen Lee here.

ASSISTANT: Please be on hold.

USER: Sure, I will wait.

ASSISTANT: There is no reservation found on your name in our database to change it.

USER: Ok, not an issue.Thank you for your information.

ASSISTANT: Thank you.