Knox Warranty Void 1 (0x0400)

Hello, just bought a new Galaxy S6 with SFR France firmware. Downloaded and installed my country firmware (Romania) to get rid of SFR bloat. flashed via Odin (Knox was 0), reboot to recovery then it showed error dm-variety failed or something like that. I wiped system and cache, reboot again, waited and configured the settings and just to be sure I rebooted the phone in Odin mode and it showed Knox Warranty Void 1 (0x0400). why did that happened? Didn't try to root or install custom firmware, only official stock firmware from sammobile. anything I can do in this case?:(