1) Download and install the latest version of Camera Hub from http://www.elgato.com/downloads
2) Close any programs and applications that may use Elgato Cam Link 4K. For example OBS Studio, Xsplit, Zoom, Teams, Slack.
3) Open Camera Hub.
4) Press and hold the CTRL key (Windows) / Command Key (macOS) on your keyboard, and while doing so click on the settings button.
5) Release the keyboard key, and click on "Update Firmware..."
6) If a newer firmware update is available, begin the update.
Important: Do not disconnect Elgato Cam Link 4K, quit Camera Hub, or shut down your computer while the update is in progress.
7) Once the update is complete, the Elgato Cam Link 4K should automatically restart and appear in Camera Hub.