If you are seeing this error message "The Kisi Controller is not available", it means that your Kisi Controller is offline.
Usually, when this happens, it is due to either network or power issues at your location. If you are an admin or manager of your organization, please see Troubleshooting Guide - Kisi Controller. If you are not an admin of the organization and are receiving this error, please contact your organization admin for assistance.
For more information on potential door unlock failures, please see this article.