You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I am Debra Lewis. Can you please help me in changing my existing reservation, due to personal issue?

ASSISTANT: Sure, I am glad to help you. Please wait for while.

USER: Thank you. Sure.

ASSISTANT: Thanks for your time, there is no reservation found on your name in our database.

USER: Ok, that's not a problem. Anyhow, thanks for the information.

ASSISTANT: Thank you for choosing us.