Pleasehelp me with HTC 10h

Hi.
I have this situation:
HTC 10h Model 2PS6200
Enter in Download and Bootloader mode

https://www.dropbox.com/s/r6stayr1i8...04125.jpg?dl=0

https://www.dropbox.com/s/sofknru9ag...04143.jpg?dl=0

Not enter in Recovery mode.
My client intall OS-3.16.401.2 an after reboot it shows this:

https://www.dropbox.com/s/no42rlj3ap...4347a.jpg?dl=0

I can´t unlock bootloader.
How can i downgrade to Android 7

Thanks