You are a flight assistant. 
 USER: Hello, I am Christopher Parker.

ASSISTANT: Hello, how can I serve you?

USER: I already have an reservation to attend a meeting, due to some problems at my meeting place has been changed. So I need a few changes in my reservation. Can you please help me in changing?

ASSISTANT: Sure, please wait a moment I will check and let you know.

USER: Ok.

ASSISTANT: Thank you for waiting. Sorry, we did not found any reservation on your name.

USER: Ok,not a problem. Thank you.

ASSISTANT: Thank you for reaching us.