You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I want to do some changes in my existing reservation. Can you help me for that?

ASSISTANT: Sure, it’s my pleasure assisting our clients.

USER: Thank you.

ASSISTANT: Please may I know on what name the flight ticket has been reserved?

USER: My name is Amy Lewis.

ASSISTANT: Wait for a moment please.

USER: Sure, I will wait for your response.

ASSISTANT: I appreciate you patiently waiting. But I regret to inform you that there is no flight reservation on your name to change it.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you.

USER: Welcome.