How to automate slot selection after android AB-Update

How to automate slot selection after android AB-Update fastboot get active slot active The Power H922 server supports a maximum of 32 DDR4 fast boot times and is ideally suited to contain the rootvg of Virtual IO fastboot getvar currentslot So i decided to flash twrp into a boot slot via fastboot then, i set the active-slot to that but then I still don't get twrp idk why Now, I can get into

fastboot getvar currentslot active The Power H922 server supports a maximum of 32 DDR4 fast boot times and is ideally suited to contain the rootvg of Virtual IO

fastboot set active slot stack trace: Error: failed to set active slot: Error: {error:{code:1,cmd:fastboot --set-active=b},stderr: waiting for any device > Display a bootloader variable fastboot set_active suffix: Sets the active slot If slots are not supported, this does nothing fastboot boot