There is a new update for these phones, and as soon as the phone is updated, the test point mode is locked
I mean, if you try to enter the phone into HUAWEI COM 1.0 mode, and despite the safety of the USB socket, it will not enter this mode and will not detected on the computer.(no detected voice)
After the update, the test point mode will be closed, and if you connect the phone and do a test point, the computer will never detected it
In this case, it will read normally in Fastboot mode or Upgrade mode
If you try to do a downgrade, all modes will be closed, meaning the phone will not detected in Upgrade Mode, Fastboot mode, or Test Point mode after downgrade.
SOLUTION TO FIX PHONE ,
after downgrade, you can do Upgrade and flash the latest version 11, and phone will return to reading FastBot and Upgrade Mode