Turn it off by going to a different (unsupported) mode on the monitor like Photo - then turn it back to Gaming- Freesync? Then make sure it is still set in the control panel?
Yeah it's all set, tried that, flat out does not work in FREESYNC mode. I switched back to 16.9.2 and it works. They dropped the ball a bit, new features are nice, but you can't break FreeSync.