I think this error occurs when you try to downgrade the bootloader. The 5th number of CSC reading from the right side is the bootloader version. That number of new firmware should be equal or greater than the one from the current firmware.Edit: I've realized I wasn't actually bootloader unlocked once I say this post: https://forum.xda-developers.com/t/how-to-unlock-bootloader.4244757/post-85085247
I've followed every step, and had success until... the very last one where Odin throws an error when flashing to PDA with the new boot.img.tar - "NAND Write Start!!" / RQT_CLOSE!!" in Odin and "SW REV CHECK FAIL : [boot]" "Fused 1 > Binary 0" and "SECURE CHECK FAIL : : boot" on the phone in download mode.
I'd really appreciate any tips on what I'm doing wrong...