If your device says "No update found" but you are experiencing bugs, you may need a specific push from ZTE.
In this guide, I’ll walk you through where to find official firmware, how to identify your correct hardware version, and the safest way to perform the update. Zte Mu5001 Firmware Download
By staying informed and up-to-date with the latest firmware, you can get the most out of your ZTE MU5001 device and enjoy a reliable and secure mobile broadband experience. If your device says "No update found" but
Chinese versions use Baidu servers. Go to http://192.168.0.1 – the update button will redirect to a Chinese ZTE cloud link. You will need a Baidu account to download. Zte Mu5001 Firmware Download