You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello.

USER: I am Katherine Brown.

ASSISTANT: In what way can I help you?

USER: Please, help me in changing my earlier reservation.

ASSISTANT: Sure, hold on.

USER: Sure.

ASSISTANT: Thanks for waiting. No reservation was found with your name.

USER: Ok. Thank you for quick response.

ASSISTANT: Thank you for your time with us.