You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I would like to change my existing reservation, please help me out.

ASSISTANT: Ok, may I know your name please.

USER: My name is Amy Martin.

ASSISTANT: Amy Martin, thank you for waiting. There is no reservation found by your name.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Thank you for reaching our services. Have a nice day.