Patched - Se Bootloader Unlocking Relocking 1662

Then, and only then, can you run fastboot oem lock (or the device-specific command). But if the 1662 patch was applied via a firmware update, the exploit chain is broken—and any attempt to relock may permanently disable the device.

: Unlike previous updates where a factory reset or a downgrade could revert the bootloader's behavior, the 1662 patch modifies the TrustZone/TEE (Trusted Execution Environment). This makes the restriction persistent even across software downgrades. Why the Change? se bootloader unlocking relocking 1662 patched

Unlocking the bootloader on a patched device can trip Knox, void your warranty, permanently disable some Samsung features (Samsung Pay, Secure Folder, etc.), and may brick your device if done incorrectly. Proceed at your own risk. Then, and only then, can you run fastboot