You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: Can you please help me to change my reservation?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Can I know your name please?

USER: I am Brandon Moore.

ASSISTANT: Sorry to inform you that there is no active reservation found on your given name.

USER: Ok, not a problem. Thank you.

ASSISTANT: Thanks for contacting us.