1.To avoid the spread of virus inside the firmware, which could result in damage to the ANTMINER S19 sequence, the location operate of “Protected Boot” has been switched on and also the “Root Authority” perform continues to be disabled. If approved, your refund will probably be processed inside seven days. https://antminerbitmains19pro110t63949.kylieblog.com/35084956/bitmain-antminer-s21-hyd-options