For SmartStart (SS), you need to scan the z-wave QR via the Hubitat mobile/phone app, not just your plain camera app (which is presumably how you got to Samsung SmartSwitch site?)
SS documentation here (link will automatically scroll to proper section).
I also recommend using Jeff P's helpful SS hub-app to manage SS devices -- more info here -- the second post of that thread contains helpful pairing tips and troubleshooting tips.
ETA -- it's frustrating that device packaging these days includes 2 or more QR codes all over it for different things -- the SS QR will commonly also say DSK and spell out the 1st 5 digits of the DSK # (not always, but that's a pretty common tell for the SS QR).
