You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Cynthia Miller. Can you help me in changing my previous reservation?

ASSISTANT: Yes, I can help you. Give me a moment.

USER: Ok.

ASSISTANT: Sorry to say that there is no reservation found on your name.

USER: That's fine. Anyway, thank you for your help.

ASSISTANT: Thank you for reaching our agency.