You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you for the day?

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

ASSISTANT: Sure, I am here to help you. Please wait for a moment.

USER: Sure.

ASSISTANT: Sorry, we found no reservation on your given name.

USER: That's ok. Thank you for your time.

ASSISTANT: Thank you for reaching us.