If you have a windows machine type in your internet search bar for the Samsung smart switch and when you click on the link it will give a few versions of the smart switch for Mac, windows and I think two other platforms. Select the one you need and download the install. Once you've installed it and got it set up restart your computer it will prompt you too and then open smart switch. Then connect your phone.
They'll be a restore or a backup option you can back up first if you haven't already saved to Google drive or Samsung drive with your back up to restore after. As rolling back or downgrading will wipe and restart your device as from new factory reset if you like.
Once you've done that after a bit of a pause takes a while for the software to recognise but then the downgrade button will appear at the bottom of that same window. Press that and it starts the process. Just follow it from there.
