You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I need your help in making few changes in my recent booking.

ASSISTANT: Sure, to make change I need your name, can you please share it?

USER: My name is Karen Campbell.

ASSISTANT: Please wait, I will check your reservation and revert back to you.

USER: Sure.

ASSISTANT: I am unable to find your reservation in our system.

USER: Oh. That's Ok.

ASSISTANT: Thank you for reaching us.