ΟΚ θα μπεις θα ξεκλειδώσεις και μετά...
βρηκα αυτό
I suggest you to try as follow.
-official 8.12.13 via MIflash and boot into it. προσοχη σε arb
-twrp 1102
-flash and BOOT on 8.12.20 EU rom.
_if OK you flash 9.1.3 xtrv-eu (if you can't download it) or 9.1.24 you got.
-twrp 1227 before boot up.
you should succeed.