Separation Alert for Apple Watch

I'm trying to set up a separation alert for my Apple Watch (Series 4, Watch OS 8.6). I don't wear my watch around the house but want to wear it when I go out. I often forget to put it on and would like to get an alert on my iPhone (11 Pro Max, OS15.5) if I leave without my watch.

When I open FindMy on my iPhone and choose Devices>Apple Watch, I don't see "Notify When Left Behind," only "Notify When Found."

Will separation alert not work because my watch is too old a series? It did update to the latest Watch OS.