FAILED (remote: 'Fastboot command is not allowed

FAILED (remote: 'Fastboot command is not allowed fastboot change slot stack trace: Error: failed to set active slot: Error: {error:{code:1,cmd:fastboot --set-active=b},stderr: waiting for any device > fastboot get active slot First you need the actual fastboot, 3 Then the correct command is: fastboot --set-active=a

fastboot get active slot From there you can run fastboot getvar current-slot to see which slot you are on And you can change slots using fastboot --set-active=the slot

fastboot change slot --slot SLOT Override the default behavior and prompt fastboot to flash the slot that is passed in as an argument --set-active I guess your bootloader is unlocked? Did you try to change the active slot? Get the current active boot slot: fastboot getvar current-slot