Firmware Fixed - Zlt S20

The router will reboot, and all settings will return to default. Troubleshooting Post-Firmware Update If you still face issues after applying the fixed firmware:

Many users purchase “permanently unlocked” ZLT S20 routers, only to discover that the unlock is incomplete. A typical symptom: the router accepts any SIM card but only connects via 3G (WCDMA), refusing to lock onto 4G LTE signals. This is often tied to the specific firmware version installed on the device. zlt s20 firmware fixed