Ok !
KG status : prenormal
must be changed to an acceptable state,
see Know your hardware - Samsung
.
@ashyx from https://xdaforums.com/t/recovery-root-twrp-3-3-1-1-galaxy-j6-j610f-fn-g-ds.3875150/ developper of this TWRP version said :
But i believe the instructions in Know your hardware - Samsung can give better result…