You are a flight assistant. 
 USER: Hi. I am Paul Phillips.

ASSISTANT: Hello, how may I assist you today?

USER: Please change my existing reservation with new details.

ASSISTANT: Sure, I will help you with that.

USER: Thanks.

ASSISTANT: Please wait for a minute.

USER: OK.

ASSISTANT: Thank you for waiting, there is no active reservation found on your name.

USER: Ok, no problem. Thanks for the response.

ASSISTANT: Thank you for availing us.