[Wolf-HRB]

Your problem is easy to solve. In my opinion, the reason causes this is some thing wrong within the Super partition (this device uses VAB). if you are stuck in fastboot mode (fastboot devices command works), you can easily flash boot, super, recovery and all other partitions. Since there is no security check for all BOOX devices, you do not need to worry about unlock BL or OEM lock. I have the partition images you need to solve your problem, simply contact me here and I will provide you. When you contact me, I can tell you what is the detail steps to solve this issue.