Log into your router, go to Management > Firmware Upgrade . If a new version is available, you may be able to click Check for Updates .
Ensure the firmware matches your specific hardware version (e.g., vs. F680) to avoid hardware incompatibility. Zte Zxhn F670l Firmware Update
Before attempting a manual update, you must understand how ZTE distributes firmware. Log into your router, go to Management > Firmware Upgrade
If possible, connect the ONT to a UPS (Uninterruptible Power Supply) to prevent power outages during the update process. Log into your router
A progress bar will appear. during this time.