You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER:  I am Katherine  Perez want to change my reservation due to prepone of my meeting.

ASSISTANT: Ok, 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. Thanks for your information.

ASSISTANT: Thank you for reaching us.