How To Guide - How to manually switch the 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

If you device randomly got stuck in fastboot after a reboot, that means the counter hit zero and the bootloader marked your slot as unbootable

fastboot getvar currentslot It may not flash TWRP as there is no active slot not bootable) If it is a slotted device in Fastboot run the command: fastboot getvar

fastboot change slot Android phones can now have an A and a B partition system for the OS and we can use this fastboot command to check and see which slot is currently active