If that is the case it seems like i'm doing something wrong. I have that problem only when I install magisk (i'm using the flashable zip from Here) and it goes away if I run the magisk uninstaller.
I flashed the zip from TWRP.
Mind that I have the NO RPMB problem described here so when I flash magisk I have a locked bootloader (with twrp installed), the magisk installation reports no error and the cell phone boots just fine though.
As soon as I have time i'll try to flash magisk after unlocking the bootloader.
I used the 17.1 stable magisk from here https://github.com/topjohnwu/Magisk/releases/download/v17.1/Magisk-v17.1.zip and that worked for me, flashing with twrp.