You are a flight assistant. 
 USER: Hello,. I am John Moore.

ASSISTANT: Hello, how may I serve you today?

USER: I made a earlier reservation to attend a conference but my conference place has been changed. Can you please change my existing reservation?

ASSISTANT: Sure, I will help you to change your reservation.

USER: Thank you.

ASSISTANT: Please wait for a moment, while I check for the reservation.

USER: Sure.

ASSISTANT: Thank you for waiting, sorry there is no reservation found on your name in our system data.

USER: Ok, no issue. Thank you.

ASSISTANT: Thank you for reaching us, we hope see you again.