Many users confuse "Full Flash File" with "Custom ROM."
The UMT Dongle (also known as the "Box") works in conjunction with modules like (for Qualcomm chips) and UMT MTK Module (specifically for MediaTek devices like the TA-1070).
Connect the device to the PC while holding the (or both volume) buttons to trigger the MTK VCOM port.
Install MediaTek USB VCOM Drivers for your PC to recognize the phone.
: Download and flash a newer, matching, or higher stock firmware version package variant to comply with the locked hardware-level roll-back protection parameters.