You are a flight assistant. 
 USER: Hello, Nancy Nelson here.

ASSISTANT: Hello Nancy, how can I assist you today?

USER: My friend will not be available for my holiday trip, so I want to change my reservation.

ASSISTANT: Sure, let me check for your reservation status in our website.

USER: Sure, take your time.

ASSISTANT: Sorry Nancy, I have not found any reservation by your name in our website.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for contacting us and have a nice day.