You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you today?

USER: I am Lisa Williams. Could you help me to change my reservation?

ASSISTANT: Sure, please wait for a few minutes.

USER: Sure.

ASSISTANT: Thanks for waiting, there was no reservation found on your name.

USER: Ok, thank you for informing me.

ASSISTANT: Thank you for availing us.