You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, what can I aid you?

USER: My name is Scott Collins, I just need your help in changing my existing reservation details.

ASSISTANT: Yes, I will help you with it. Please give me a moment to check the reservation status.

USER: Ok, take your time.

ASSISTANT: Sorry Collins, there is no reservation found under your name in our database.

USER: It's ok, thank you for the information.

ASSISTANT: Most welcome, hope you have a great day.