Can't unlock bootloader (Redmi Note 8 Pro, MT6785)

[Gius06G]

I cannot unlock bootloader on this Redmi Note 8 Pro, it's bricked and I need to unlock bootloader, but no luck:
Command python3 mtk.py da seccfg unlock (same with --preloader option)
Output:
...Port - Device detected :)
Preloader - CPU: MT6785(Helio G90)
Preloader - HW version: 0x0
Preloader - WDT: 0x10007000
Preloader - Uart: 0x11002000
Preloader - Brom payload addr: 0x100a00
Preloader - DA payload addr: 0x201000
Preloader - CQ_DMA addr: 0x10212000
Preloader - Var1: 0xa
Preloader - Disabling Watchdog...
Preloader - HW code: 0x813
Preloader - Target config: 0xe7
Preloader - SBC enabled: True
Preloader - SLA enabled: True
Preloader - DAA enabled: True
Preloader - SWJTAG enabled: True
Preloader - EPP_PARAM at 0x600 after EMMC_BOOT/SDMMC_BOOT: False
Preloader - Root cert required: False
Preloader - Mem read auth: True
Preloader - Mem write auth: True
Preloader - Cmd 0xC8 blocked: True
Preloader - Get Target info
Preloader - BROM mode detected.
Preloader - HW subcode: 0x8a00
Preloader - HW Ver: 0xca00
Preloader - SW Ver: 0x0
Preloader - ME_ID: AF588F9FED9850F7798943DDD956205C
Preloader - SOC_ID: 1098111BEF7A62356ED98FFA25D82415FBE11AFB74B0F5D32CA0E32D736607B6
Preloader
Preloader - [LIB]: Auth file is required. Use --auth option.
DaHandler - Device is protected.
DaHandler - Device is in BROM-Mode. Bypassing security.
PLTools - Loading payload from mt6785_payload.bin, 0x264 bytes
Exploitation - Kamakiri Run
Exploitation - Done sending payload...
PLTools - Successfully sent payload: /home/giusix06_jr/mtkclient-main/mtkclient/payloads/mt6785_payload.bin
Port - Device detected :)
DaHandler
DaHandler - [LIB]: Device is in BROM mode. No preloader given, trying to dump preloader from ram.
DAXFlash - Uploading xflash stage 1 from MTK_DA_V5.bin
XFlashExt - Patching da1 ...
Mtk - Patched "hash_check" in preloader
Mtk - Patched "get_vfy_policy" in preloader
XFlashExt - Patching da2 ...
XFlashExt - Security check patched
XFlashExt - DA version anti-rollback patched
XFlashExt - SBC patched to be disabled
XFlashExt - Register read/write not allowed patched
DAXFlash - Successfully uploaded stage 1, jumping ..
Preloader - Jumping to 0x200000
Preloader - Jumping to 0x200000: ok.
DAXFlash - Successfully received DA sync
DAXFlash - Sending emi data ...
DAXFlash - DRAM setup passed.
DAXFlash - Sending emi data succeeded.
DAXFlash - Uploading stage 2...
DAXFlash - Upload data was accepted. Jumping to stage 2...
DAXFlash
DAXFlash - [LIB]: Stage was't executed. Maybe dram issue ?.
DAXFlash
DAXFlash - [LIB]: Error on booting to da (xflash)

OS: Debian 12.7 Bookworm, Xfce 4.18 Desktop