Fix Failed to Boot into Userspace Fastboot, One or more

It can be very useful to know if partition slot A or slot B is currently active and you can learn

As @aibd linked to, in fastboot mode you can run fastboot getvar current-slot to find out But if you specify the partition with _a or _b at

fastboot getvar currentslot failed with error code 2 You can use the below tables to identify the devcmd and error strings found in the logs devcmd #, devcmd string 1

fastboot change slot AB devices don't have a recovery partition OP needs to do 'fastboot boot > and then flash the installation zip