You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: My name is Rebecca Brown. I would like to change my reservation, could you help me out?

ASSISTANT: Sure, hold on for a moment.

USER: Sure.

ASSISTANT: Sorry, no reservation found for the given name.

USER: That's ok.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your help.