You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I aid you?

USER: My brother told me to change his reservation, can you please help me out?

ASSISTANT: Sure, may I know your brother's name?

USER: His name is Benjamin Johnson.

ASSISTANT: Please hold on for a while.

USER: Sure.

ASSISTANT: Sorry Johnson, no reservation is available on this name.

USER: No problem, thank you for checking.

ASSISTANT: Thank you for reaching us.