Disclaimer: Always download firmware from official sources. The author is not responsible for bricked devices. When in doubt, contact ZTE support or your carrier.
Check the sticker under the battery or on the back cover for one of these common variants: Zte Mu5001 Firmware Download
Check your carrier’s update log for the most current numbers. Problem: “Firmware update failed” at 99% Fix: Use a wired USB-C connection to your PC, then retry. Wi-Fi interference can corrupt the transfer. Disclaimer: Always download firmware from official sources