no need to downgrade & no need disassemble or testpoints, simply use preloader method, unlock bootloader & write security..
Selected model: Realme RMX3710 (Realme C55)
Operation: Repair
Software version: 6.5
Work ID: 21492197
Connect phone in PRELOADER Mode
Waiting for device... OK
Driver: [MediaTek Inc.,wdm_usb,MediaTek PreLoader USB VCOM_V1632 (Android),usb2ser.sys,3.0.1504.0]
Device found at COM25 [PRELOADER]
Open port... OK
Send start cmd... OK
Get HW code from device... 0707
Get sec config... OK [00000005]
Active sec flags: [SBC DAA]
Get HW & SW version from device... OK
HW VER: CA00, SW VER: 0000, HW SUB CODE: 8A00
Detect chip [MT6768]
Library Version [2]
Select platform... OK
Init BROM... OK
Force Charge... OK
Disable WatchDog Timer... OK
Reopen port for libver2... OK
Preloader exist. Skip connection verification.
Get ME ID... OK
ME_ID = 0xC69BC202, 0x53D76976, 0xDAACFAA7, 0xE80E35E8
Load DownloadAgent... OK
Search DA... OK [1]
Send bootloader... OK
Start bootloader... OK
Wait for answer from bootloader... OK
Send SYNC signal... OK
Setup device enviroment... OK
Setup device parametres... OK
Receive DA SYNC signal... OK
Set DA parametres... OK
Get device connection agent... [PRELOADER]
Preloader alive. Skip initializing external RAM
Get device info... OK
EMMC_ID: 0x9B01005930533235360081B556C17AF7
Send preloader... OK
Load DownloadAgent... OK
Search DA... OK [8]
Send 2nd DA... OK
Get device info... OK
EMMC INFO:
EMMC_CNAME: Y0S256
EMMC_ID : 0x9B01005930533235360081B556C17AF7
EMMC_BOOT1: 0x0000400000 (4.00Mb)
EMMC_BOOT2: 0x0000400000 (4.00Mb)
EMMC_RPMB : 0x0001000000 (16.00Mb)
EMMC_USER : 0x3A3E000000 (232.97Gb)
RAM INFO:
INT_SRAM: 0x0000070000 (448.00Kb)
EXT_RAM : 0x0100000000 (4.00Gb)
Checking USB status... USB_HIGH_SPEED
[EFUSE INFO]: BROM not disabled
Read partitions info from phone... OK
Checking A/B state... OK
Read product info... [EROFS] ... OK
Product Brand : oplus
Product Manufacturer : oplus
Product Model : RMX3710
Product Name : ossi
Product Device : REE2ADL1
Product Board : k69v1_64_k419
Board Platform : mt6768
Build ID : SP1A.210812.016
Build Date : Wed Jan 17 10:41:03 CST 2024
Display ID : RMX3710_11_A.01
Security Patch : 2024-01-05
Version SDK : 33
Version Release : 13
Version Codename : REL
Firmware Version : 1706528407505
Read security partition from phone...
Decrypting security data... OK
Encrypt security data... OK
Read partition "nvdata"... OK
Read partition "protect1"... OK
Read partition "nvram"... OK
Read NVDATA files... OK
Read NVRAM files... OK
Read security files... OK
Calculating... OK
Repairing IMEI...
IMEI 1: 111111111111119
IMEI 2: 111111111111119
Write IMEI and patch CERT [NVDATA]... OK
Checking patch type... [1]
Patching CERT... already patched, skip
Updating NVRAM... OK
Read security partition from phone... OK
Write security partition to phone... OK
Checking additional lock... [DISABLED]
Selected "Disable VBMETA verification"
Read security partition from phone... OK
Write security partition to phone... OK
Write IMEI and patch CERT [NVRAM]... OK
Write partition "nvdata"... OK
Write partition "nvram"... OK
Repair Security and Patch cert done!
If your phone after repair keeps rebooting - use wipe data option.