Follow this steps
1. boot to fastboot mode (power +vol down)
2.from ADB cmd fastboot flash vbmeta vbmeta.img
3. from ADB cmd fastboot boot twrp-3.3.1-test0-toco-mauronofrio.img (you can rename it to twrp.img) -LINK BELOW
4. in twrp: wipe-> format data -> yes
5. in twrp -> reboot to bootloader...