Unable to recognize the HiKey960 as a FastBoot device after recovery step

I’m a beginner, so this may be an elementary question…

I want to simply recover my HiKey board.
However, if I follow the [Procedure referenced].
My host machine is stuck in a stuck state where it repeatedly detects and loses connections to the HiKey.
I think HiKey is stuck and looping on the boot.

What can be done to resolve this?

[Procedure referenced]

[Board model]
HiKey 960 Consumer Edition

[Host Machine Configuration]
Windows 10 64Bit Home
VirtualBox 6.1
Ubuntu 14.04 LTS
Using VirtualBox, Windows as the host OS and Ubuntu as the guest OS It operates as.

[Work step]

  1. set HiKey’s DipSwitch to recovery mode.
  2. connect usb cable to HiKey and host machine.
  3. Windows detects HiKey connection.
  4. from the USB menu of VirtualBox, select HiKey (which is detected as ”HISILICON USB SER”) and switch the connection to the Ubuntu side.
  5. Run the following command to write “hikey_idt” to HiKey.
    $ sudo . /hikey_idt -c config -p /dev/ttyUSB0
  6. confirmed that “Finish downloading” displayed and process completed.
  7. powering off the HiKey.
  8. set HiKey’s DipSwitch to fastboot mode everytime.
  9. powering up the HiKey.
  10. Windows repeats the HiKey connection “detects” and “lost”.
    This time Ubuntu does not recognize HiKey and cannot switch between them.

detect HiKeys as FastBoot devices in Ubuntu.

Here’s the complete log when writing hikey_idt to the HiKey

user@user-VirtualBox:~/share/hikey960- bootLoader$ sudo . /hikey_idt -c config -p /dev/ttyUSB0
Config name: config
Port name: /dev/ttyUSB0
0: Image: hisi-sec_usb_xloader.img Downalod Address: 0x20000
1: Image: hisi-sec_uce_boot.img Downalod Address: 0x6a908000
2: Image: recovery.bin Downalod Address: 0x1ac 00000
Serial port open successfully!
Start downloading hisi-sec_usb_xloader.img@0x 20000…
file total size 99584
downlaod address 0x20000
Finish downloading
Start downloading hisi-sec_uce_boot.img@0x6a 908000…
file total size 23680
downlaod address 0x6a908000
Finish downloading
Start downloading recovery.bin@0x1ac00000…
file total size 1179648
downlaod address 0x1ac00000
Finish downloading