Just registered my SS Galaxy Watch SM-R800 that I have had for 5 years. Model and Serial in the watch matched what is on their website and the registration resolved it to
Samsung Galaxy Watch 46mm SM-R800 Bluetooth GPS Smartwatch Silver Grade A + CHRG 8801643396480 | eBay
Wireless Charger Charging Dock Fit for Samsung Galaxy Watch 42mm 46mm, Replacement Charging Cradle Stand Fit for Samsung Galaxy Smart Watch SM-R800 SM-R805 SM-R810 SM-R815 - Walmart.com
Amazon.com: Samsung Galaxy Watch (46mm) Silver (Bluetooth), SM-R800 – International Version RENEWED : Cell Phones & Accessories
Best Buy: Samsung Galaxy Watch Smartwatch 46mm Stainless Steel Silver SM -R800NZSAXAR