You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you?

USER: I am Katherine Lewis, want to alter my recent reservation due to sudden changes in my plan. Can you please help me out with that?

ASSISTANT: Ok, please wait I will revert you in a moment.

USER: Sure.

ASSISTANT: Sorry to inform you that no reservation was found on your name in our data base.

USER: It's ok, thank you for your help.

ASSISTANT:  Thank you for availing us.