You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello,.

USER: I am Karen Moore.

ASSISTANT: How may I help you?

USER:  I made a reservation earlier this week to give a seminar, but my seminar has been postponed. Please, help me in changing my reservation.

ASSISTANT: Sure, please be on hold.

USER: Sure.

ASSISTANT: Thank you for your time. Sorry, no reservation found in your given name.

USER: Ok, thank you.

ASSISTANT: Thank you for reaching us.