While holding the reset button, plug the router into your PC using a USB-to-USB cable (if supported by your hardware variant) or via specific LAN configurations.
Navigate to Settings , System Settings , or Administration to find the firmware update option. Install Update: zlt p21 firmware update install
Note: Do not extract the file unless explicitly instructed by the firmware documentation. Keep it saved in an easily accessible folder on your computer, like your Desktop. Step 2: Access the ZLT P21 Web User Interface (WebUI) While holding the reset button, plug the router
To provide accurate instructions for installing firmware on a (often a 4G/5G CPE router, common with carriers like Vodafone, Optus, or Telstra), please clarify: Keep it saved in an easily accessible folder
After the reboot, log back in and check the "Device Information" page to ensure the firmware version number has changed.