You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER:  I already have an reservation to attend a meeting, due to some problems meeting place has been changed. So I need a few changes in my reservation.

ASSISTANT: Sure, I am here to help you out.

USER: Thanks for accepting my request.

ASSISTANT: Wait a moment please.

USER: Sure, my name is Brenda Johnson. I will wait for your response.

ASSISTANT: we regret to inform you that there is no reservation found on your name in our records.

USER: Ok, no worries. Thank you for your information.

ASSISTANT: Thank you for choosing us.